add jinja2-based renderer for object diagrams

api/od.py

@@ -104,6 +104,7 @@ class ODAPI:
                     result.append(i)
         return result
 
+    # Returns list of tuples (name, obj)
     def get_all_instances(self, type_name: str, include_subtypes=True):
         if include_subtypes:
             all_types = self.cdapi.transitive_sub_types[type_name]

concrete_syntax/graphviz/renderer.py

@@ -1,26 +1,55 @@
+import functools
 from uuid import UUID
+from api.od import ODAPI
 from services import scd, od
 from services.bottom.V0 import Bottom
 from concrete_syntax.common import display_value, display_name, indent
 
+# Turn ModelVerse/muMLE ID into GraphViz ID
+def make_graphviz_id(uuid, prefix="") -> str:
+    result = 'n'+(prefix+str(uuid).replace('-',''))[24:] # we assume that the first 24 characters are always zero...
+    return result
 
-def render_object_diagram(state, m, mm, render_attributes=True, prefix_ids=""):
+def render_object_diagram(state, m, mm,
+    render_attributes=True, # doesn't do anything (yet)
+    prefix_ids="",
+    reify=False, # If true, will create a node in the middle of every link. This allows links to be the src/tgt of other links (which muMLE supports), but will result in a larger diagram.
+    only_render=None, # List of type names or None. If specified, only render instances of these types. E.g., ["Place", "connection"]
+    type_to_style={}, # Dictionary. Mapping from type-name to graphviz style. E.g., { "generic_link": ",color=purple" }
+    type_to_label={}, # Dictionary. Mapping from type-name to callback for custom label creation.
+):
     bottom = Bottom(state)
     mm_scd = scd.SCD(mm, state)
     m_od = od.OD(mm, m, state)
+    odapi = ODAPI(state, m, mm)
 
-    def make_id(uuid) -> str:
-        return 'n'+(prefix_ids+str(uuid).replace('-',''))[24:]
+    make_id = functools.partial(make_graphviz_id, prefix=prefix_ids)
 
     output = ""
 
     # Render objects
     for class_name, class_node in mm_scd.get_classes().items():
+        if only_render != None and class_name not in only_render:
+            continue
+
+        make_label = type_to_label.get(class_name,
+            # default, if not found:
+            lambda obj_name, obj, odapi: f"{display_name(obj_name)} : {class_name}")
+
+        output += f"\nsubgraph {class_name} {{"
+
         if render_attributes:
             attributes = od.get_attributes(bottom, class_node)
 
+
+        custom_style = type_to_style.get(class_name, "")
+        if custom_style == "":
+            output += f"\nnode [shape=rect]"
+        else:
+            output += f"\nnode [shape=rect,{custom_style}]"
+
         for obj_name, obj_node in m_od.get_objects(class_node).items():
-            output += f"\n{make_id(obj_node)} [label=\"{display_name(obj_name)} : {class_name}\", shape=rect] ;"
+            output += f"\n{make_id(obj_node)} [label=\"{make_label(obj_name, obj_node, odapi)}\"] ;"
             #" {{"
 
             # if render_attributes:
@@ -31,17 +60,46 @@ def render_object_diagram(state, m, mm, render_attributes=True, prefix_ids=""):
             #             output += f"\n{attr_name} => {display_value(val, type_name)}"
             # output += '\n}'
 
+        output += '\n}'
+
     output += '\n'
 
     # Render links
     for assoc_name, assoc_edge in mm_scd.get_associations().items():
+        if only_render != None and assoc_name not in only_render:
+            continue
+
+        make_label = type_to_label.get(assoc_name,
+            # default, if not found:
+            lambda lnk_name, lnk, odapi: f"{display_name(lnk_name)} : {assoc_name}")
+
+        output += f"\nsubgraph {assoc_name} {{"
+
+        custom_style = type_to_style.get(assoc_name, "")
+        if custom_style != "":
+            output += f"\nedge [{custom_style}]"
+        if reify:
+            if custom_style != "":
+                # created nodes will be points of matching style:
+                output += f"\nnode [{custom_style},shape=point]"
+            else:
+                output += "\nnode [shape=point]"
+
         for link_name, link_edge in m_od.get_objects(assoc_edge).items():
             src_obj = bottom.read_edge_source(link_edge)
             tgt_obj = bottom.read_edge_target(link_edge)
             src_name = m_od.get_object_name(src_obj)
             tgt_name = m_od.get_object_name(tgt_obj)
 
-            output += f"\n{make_id(src_obj)} -> {make_id(tgt_obj)} [label=\"{display_name(link_name)}:{assoc_name}\"] ;"
+            if reify:
+                # intermediary node:
+                output += f"\n{make_id(src_obj)} -> {make_id(link_edge)} [arrowhead=none]"
+                output += f"\n{make_id(link_edge)} -> {make_id(tgt_obj)}"
+                output += f"\n{make_id(link_edge)} [xlabel=\"{make_label(link_name, link_edge, odapi)}\"]"
+            else:
+                output += f"\n{make_id(src_obj)} -> {make_id(tgt_obj)} [label=\"{make_label(link_name, link_edge, odapi)}\", {custom_style}] ;"
+
+        output += '\n}'
 
     return output
 
@@ -50,10 +108,8 @@ def render_trace_match(state, name_mapping: dict, pattern_m: UUID, host_m: UUID,
     class_type = od.get_scd_mm_class_node(bottom)
     attr_link_type = od.get_scd_mm_attributelink_node(bottom)
 
-    def make_pattern_id(uuid) -> str:
-        return 'n'+(prefix_pattern_ids+str(uuid).replace('-',''))[24:]
-    def make_host_id(uuid) -> str:
-        return 'n'+(prefix_host_ids+str(uuid).replace('-',''))[24:]
+    make_pattern_id = functools.partial(make_graphviz_id, prefix=prefix_pattern_ids)
+    make_host_id = functools.partial(make_graphviz_id, prefix=prefix_host_ids)
 
     output = ""
 

concrete_syntax/textual_od/objectdiagrams.jinja2

@@ -0,0 +1,18 @@
+{% macro render_name(name) %}{{ name if not hide_names or name.startswith("__") else "" }}{% endmacro %}
+
+{% macro render_attributes(obj) %} {
+  {% for attr_name in odapi.get_slots(obj) %}
+    {{ attr_name}} = {{ display_value(
+      val=odapi.get_slot_value(obj, attr_name),
+      type_name=odapi.get_type_name(odapi.get_slot(obj, attr_name)),
+      indentation=4) }};
+  {% endfor %}
+}{% endmacro %}
+
+{% for obj_name, obj in objects %}
+{{ render_name(obj_name) }}:{{ odapi.get_type_name(obj) }}{{ render_attributes(obj) }}
+{% endfor %}
+
+{% for lnk_name, lnk in links %}
+{{ render_name(obj_name) }}:{{ odapi.get_type_name(lnk) }} ({{odapi.get_name(odapi.get_source(lnk))}} -> {{odapi.get_name(odapi.get_target(lnk))}}){{ render_attributes(lnk) }}
+{% endfor %}

concrete_syntax/textual_od/parser.py

@@ -1,10 +1,10 @@
 # Parser for Object Diagrams textual concrete syntax
 
-from lark import Lark, logger
+from lark import Lark, logger, Transformer
 from lark.indenter import Indenter
 from api.od import ODAPI
 from services.scd import SCD
-from concrete_syntax.common import _Code, TBase
+from concrete_syntax.common import _Code
 from uuid import UUID
 
 grammar = r"""
@@ -41,11 +41,25 @@ rev_link_spec: "(" IDENTIFIER "<-" IDENTIFIER ")"
 slot: IDENTIFIER "=" literal ";"
 """
 
-parser = Lark(grammar, parser='lalr')
+parser = Lark(grammar, parser='lalr', propagate_positions=True)
+
+class DefaultNameGenerator:
+    def __init__(self):
+        self.counter = 0
+
+    def __call__(self, type_name):
+        name = f"__{type_name}_{self.counter}"
+        self.counter += 1
+        return name
 
 # given a concrete syntax text string, and a meta-model, parses the CS
 # Parameter 'type_transform' is useful for adding prefixes to the type names, when parsing a model and pretending it is an instance of a prefixed meta-model.
-def parse_od(state, m_text, mm, type_transform=lambda type_name: type_name):
+def parse_od(state,
+    m_text, # text to parse
+    mm, # meta-model of model that will be parsed. The meta-model must already have been parsed.
+    type_transform=lambda type_name: type_name,
+    name_generator=DefaultNameGenerator(), # exception to raise if anonymous (nameless) object/link occurs in the model. Main reason for this is to forbid them in LHS of transformation rules.
+):
     tree = parser.parse(m_text)
 
     m = state.create_node()
@@ -56,62 +70,95 @@ def parse_od(state, m_text, mm, type_transform=lambda type_name: type_name):
             for type_name in ["Integer", "String", "Boolean", "ActionCode"]
     }
 
-    class T(TBase):
+    class T(Transformer):
         def __init__(self, visit_tokens):
             super().__init__(visit_tokens)
-            self.obj_counter = 0 # used for generating unique names for anonymous objects
+
+        def IDENTIFIER(self, token):
+            return (str(token), token.line)
+        
+        def INT(self, token):
+            return (int(token), token.line)
+
+        def BOOL(self, token):
+            return (token == "True", token.line)
+
+        def STR(self, token):
+            return (str(token[1:-1]), token.line) # strip the "" or ''
+
+        def CODE(self, token):
+            return (_Code(str(token[1:-1])), token.line) # strip the ``
+
+        def INDENTED_CODE(self, token):
+            skip = 4 # strip the ``` and the following newline character
+            space_count = 0
+            while token[skip+space_count] == " ":
+                space_count += 1
+            lines = token.split('\n')[1:-1]
+            for line in lines:
+                if len(line) >= space_count and line[0:space_count] != ' '*space_count:
+                    raise Exception("wrong indentation of INDENTED_CODE")
+            unindented_lines = [l[space_count:] for l in lines]
+            return (_Code('\n'.join(unindented_lines)), token.line)
+
+        def literal(self, el):
+            return el[0]
 
         def link_spec(self, el):
-            [src, tgt] = el
-            return (src, tgt)
+            [(src, src_line), (tgt, _)] = el
+            return (src, tgt, src_line)
 
         def rev_link_spec(self, el):
-            [tgt, src] = el # <-- reversed :)
-            return (src, tgt)
+            [(tgt, tgt_line), (src, _)] = el # <-- reversed :)
+            return (src, tgt, tgt_line)
 
         def type_name(self, el):
-            type_name = el[0]
+            type_name, line = el[0]
             if type_name in primitive_types:
-                return type_name
+                return (type_name, line)
             else:
-                return type_transform(el[0])
+                return (type_transform(type_name), line)
         
         def slot(self, el):
-            [attr_name, value] = el
-            return (attr_name, value)
+            [(attr_name, line), (value, _)] = el
+            return (attr_name, value, line)
         
         def object(self, el):
-            [obj_name, type_name, link] = el[0:3]
+            [obj, (type_name, line), link] = el[0:3]
             slots = el[3:]
-            if state.read_dict(m, obj_name) != None:
-                msg = f"Element '{obj_name}:{type_name}': name '{obj_name}' already in use."
-                # raise Exception(msg + " Names must be unique")
-                print(msg + " Ignoring.")
-                return
-            if obj_name == None:
-                # object/link names are optional
-                #  generate a unique name if no name given
-                obj_name = f"__{type_name}_{self.obj_counter}"
-                self.obj_counter += 1
-            if link == None:
-                obj_node = od.create_object(obj_name, type_name)
-            else:
-                src, tgt = link
-                if tgt in primitive_types:
-                    if state.read_dict(m, tgt) == None:
-                        scd = SCD(m, state)
-                        scd.create_model_ref(tgt, primitive_types[tgt])
-                src_obj = od.get(src)
-                tgt_obj = od.get(tgt)
-                obj_node = od.create_link(obj_name, type_name, src_obj, tgt_obj)
-            # Create slots
-            for attr_name, value in slots:
-                if isinstance(value, _Code):
-                    od.set_slot_value(obj_node, attr_name, value.code, is_code=True)
+            try:
+                if obj != None:
+                    (obj_name, _) = obj
                 else:
-                    od.set_slot_value(obj_node, attr_name, value)
+                    # anonymous object - auto-generate a name
+                    obj_name = name_generator(type_name)
+                if state.read_dict(m, obj_name) != None:
+                    msg = f"Element '{obj_name}:{type_name}': name '{obj_name}' already in use."
+                    raise Exception(msg + " Names must be unique")
+                    # print(msg + " Ignoring.")
+                    return
+                if link == None:
+                    obj_node = od.create_object(obj_name, type_name)
+                else:
+                    (src, tgt, _) = link
+                    if tgt in primitive_types:
+                        if state.read_dict(m, tgt) == None:
+                            scd = SCD(m, state)
+                            scd.create_model_ref(tgt, primitive_types[tgt])
+                    src_obj = od.get(src)
+                    tgt_obj = od.get(tgt)
+                    obj_node = od.create_link(obj_name, type_name, src_obj, tgt_obj)
+                # Create slots
+                for attr_name, value, line in slots:
+                    if isinstance(value, _Code):
+                        od.set_slot_value(obj_node, attr_name, value.code, is_code=True)
+                    else:
+                        od.set_slot_value(obj_node, attr_name, value)
 
-            return obj_name
+                return obj_name
+            except Exception as e:
+                # raising a *new* exception (instead of adding a note to the existing exception) because Lark will also raise a new exception, and ignore our note:
+                raise Exception(f"at line {line}:\n  " + m_text.split('\n')[line-1] + "\n"+ str(e)) from e
 
     t = T(visit_tokens=True).transform(tree)
 

concrete_syntax/textual_od/renderer_jinja2.py

@@ -0,0 +1,58 @@
+import jinja2
+import os
+from uuid import UUID
+
+THIS_DIR = os.path.dirname(__file__)
+
+from api.od import ODAPI
+from concrete_syntax import common
+from services.bottom.V0 import Bottom
+from util.module_to_dict import module_to_dict
+
+def render_od_jinja2(state, m, mm):
+    bottom = Bottom(state)
+    type_model_id = state.read_dict(state.read_root(), "SCD")
+    scd_model = UUID(state.read_value(type_model_id))
+    type_odapi = ODAPI(state, mm, scd_model)
+
+    objects = []
+    links = []
+
+    to_add = bottom.read_keys(m)
+    already_added = set()
+
+    while len(to_add) > 0:
+        next_round = []
+        for obj_name in to_add:
+            obj = state.read_dict(m, obj_name)
+            src, tgt = state.read_edge(obj)
+            if src == None:
+                # not a link
+                objects.append((obj_name, obj))
+                already_added.add(obj)
+            else:
+                # A link can only be written out after its source and target have been written out
+                if src in already_added and tgt in already_added:
+                    links.append((obj_name, obj))
+                else:
+                    # try again later
+                    next_round.append(obj_name)
+        if len(next_round) == len(to_add):
+            raise Exception("We got stuck!", next_round)
+        to_add = next_round
+
+    loader = jinja2.FileSystemLoader(searchpath=THIS_DIR)
+    environment = jinja2.Environment(
+        loader=loader,
+        # whitespace control:
+        trim_blocks=True,
+        lstrip_blocks=True,
+    )
+    template = environment.get_template("objectdiagrams.jinja2")
+    return template.render({
+        'objects': objects,
+        'links': links,
+        'odapi': ODAPI(state, m, mm),
+        **globals()['__builtins__'],
+        **module_to_dict(common),
+    })

examples/petrinet/helpers.py

@@ -0,0 +1,6 @@
+from uuid import UUID
+
+def get_num_tokens(odapi, place: UUID):
+    pn_of = odapi.get_incoming(place, "pn_of")[0]
+    place_state = odapi.get_source(pn_of)
+    return odapi.get_slot_value(place_state, "numTokens")

examples/petrinet/renderer.py

@@ -1,5 +1,6 @@
 from api.od import ODAPI
 from concrete_syntax.graphviz.make_url import show_graphviz
+from concrete_syntax.graphviz.renderer import make_graphviz_id
 
 try:
     import graphviz
@@ -14,37 +15,45 @@ def render_tokens(num_tokens: int):
         return '●●\\n●●'
     return str(num_tokens)
 
-def render_petri_net(od: ODAPI):
+def render_petri_net_to_dot(od: ODAPI) -> str:
     dot = ""
     dot += "rankdir=LR;"
     dot += "center=true;"
     dot += "margin=1;"
     dot += "nodesep=1;"
-    dot += "edge [arrowhead=vee];"
-    dot += "node[fontname=Arial,fontsize=10];\n"
     dot += "subgraph places {"
-    dot += "  node [shape=circle,fixedsize=true,label=\"\", height=.35,width=.35];"
-    for _, place in od.get_all_instances("PNPlace"):
-        place_name = od.get_name(place)
+    dot += "  node [fontname=Arial,fontsize=10,shape=circle,fixedsize=true,label=\"\", height=.35,width=.35];"
+    for place_name, place in od.get_all_instances("PNPlace"):
+        # place_name = od.get_name(place)
         try:
             place_state = od.get_source(od.get_incoming(place, "pn_of")[0])
             num_tokens = od.get_slot_value(place_state, "numTokens")
         except IndexError:
             num_tokens = 0
-        dot += f"  {place_name} [label=\"{place_name}\\n\\n{render_tokens(num_tokens)}\\n\\n­\"];\n"
+        dot += f"  {make_graphviz_id(place)} [label=\"{place_name}\\n\\n{render_tokens(num_tokens)}\\n\\n­\"];\n"
     dot += "}\n"
-    dot += "subgraph transitions {"
-    dot += "  node [shape=rect,fixedsize=true,height=.3,width=.12,style=filled,fillcolor=black,color=white];\n"
-    for transition_name, _ in od.get_all_instances("PNTransition"):
-        dot += f"  {transition_name} [label=\"{transition_name}\\n\\n\\n­\"];\n"
+    dot += "subgraph transitions {\n"
+    dot += "  edge [arrowhead=normal];\n"
+    dot += "  node [fontname=Arial,fontsize=10,shape=rect,fixedsize=true,height=.3,width=.12,style=filled,fillcolor=black,color=white];\n"
+    for transition_name, transition in od.get_all_instances("PNTransition"):
+        dot += f"  {make_graphviz_id(transition)} [label=\"{transition_name}\\n\\n\\n­\"];\n"
     dot += "}\n"
     for _, arc in od.get_all_instances("arc"):
-        src_name = od.get_name(od.get_source(arc))
-        tgt_name = od.get_name(od.get_target(arc))
-        dot += f"{src_name} -> {tgt_name};"
+        src = od.get_source(arc)
+        tgt = od.get_target(arc)
+        # src_name = od.get_name(od.get_source(arc))
+        # tgt_name = od.get_name(od.get_target(arc))
+        dot += f"{make_graphviz_id(src)} -> {make_graphviz_id(tgt)};"
     for _, inhib_arc in od.get_all_instances("inh_arc"):
-        src_name = od.get_name(od.get_source(inhib_arc))
-        tgt_name = od.get_name(od.get_target(inhib_arc))
-        dot += f"{src_name} -> {tgt_name} [arrowhead=odot];\n"
-    show_graphviz(dot, engine="neato")
-    return ""
+        src = od.get_source(inhib_arc)
+        tgt = od.get_target(inhib_arc)
+        dot += f"{make_graphviz_id(src)} -> {make_graphviz_id(tgt)} [arrowhead=odot];\n"
+    return dot
+
+# deprecated
+def render_petri_net(od: ODAPI, engine="neato"):
+    show_graphviz(render_petri_net_to_dot(od), engine=engine)
+
+# use this instead:
+def show_petri_net(od: ODAPI, engine="neato"):
+    show_graphviz(render_petri_net_to_dot(od), engine=engine)

examples/petrinet/runner.py

@@ -1,12 +1,13 @@
 from state.devstate import DevState
 from api.od import ODAPI
 from concrete_syntax.textual_od.renderer import render_od
+# from concrete_syntax.textual_od.renderer_jinja2 import render_od_jinja2
 from bootstrap.scd import bootstrap_scd
 from util import loader
 from transformation.rule import RuleMatcherRewriter, ActionGenerator
 from transformation.ramify import ramify
 from examples.semantics.operational import simulator
-from examples.petrinet.renderer import render_petri_net
+from examples.petrinet.renderer import show_petri_net
 
 
 if __name__ == "__main__":
@@ -48,11 +49,15 @@ if __name__ == "__main__":
     matcher_rewriter = RuleMatcherRewriter(state, mm_rt, mm_rt_ramified)
     action_generator = ActionGenerator(matcher_rewriter, rules)
 
+    def render_callback(od):
+        show_petri_net(od)
+        return render_od(state, od.m, od.mm)
+
     sim = simulator.Simulator(
         action_generator=action_generator,
         decision_maker=simulator.InteractiveDecisionMaker(auto_proceed=False),
         # decision_maker=simulator.RandomDecisionMaker(seed=0),
-        renderer=lambda od: render_petri_net(od) + render_od(state, od.m, od.mm),
+        renderer=render_callback,
         # renderer=lambda od: render_od(state, od.m, od.mm),
     )
 

examples/petrinet/runner_export_tapaal.py

@@ -0,0 +1,35 @@
+from state.devstate import DevState
+from bootstrap.scd import bootstrap_scd
+from util import loader
+
+from examples.petrinet.translational_semantics.tapaal.exporter import export_tapaal
+
+if __name__ == "__main__":
+    import os
+    THIS_DIR = os.path.dirname(__file__)
+
+    # get file contents as string
+    def read_file(filename):
+        with open(THIS_DIR+'/'+filename) as file:
+            return file.read()
+
+    state = DevState()
+    scd_mmm = bootstrap_scd(state)
+    # Read models from their files
+    mm_cs           =         read_file('metamodels/mm_design.od')
+    mm_rt_cs        = mm_cs + read_file('metamodels/mm_runtime.od')
+    # m_cs            =         read_file('models/m_example_simple.od')
+    # m_rt_initial_cs = m_cs +  read_file('models/m_example_simple_rt_initial.od')
+    m_cs            =         read_file('models/m_example_mutex.od')
+    m_rt_initial_cs = m_cs +  read_file('models/m_example_mutex_rt_initial.od')
+    # m_cs            =         read_file('models/m_example_inharc.od')
+    # m_rt_initial_cs = m_cs +  read_file('models/m_example_inharc_rt_initial.od')
+
+    # Parse them
+    mm           = loader.parse_and_check(state, mm_cs,           scd_mmm, "Petri-Net Design meta-model")
+    mm_rt        = loader.parse_and_check(state, mm_rt_cs,        scd_mmm, "Petri-Net Runtime meta-model")
+    m            = loader.parse_and_check(state, m_cs,            mm,      "Example model")
+    m_rt_initial = loader.parse_and_check(state, m_rt_initial_cs, mm_rt,   "Example model initial state")
+
+    with open('exported.tapn', 'w') as f:
+        f.write(export_tapaal(state, m=m_rt_initial, mm=mm_rt))

examples/petrinet/translational_semantics/tapaal/exporter.py

@@ -0,0 +1,17 @@
+import jinja2
+import os
+THIS_DIR = os.path.dirname(__file__)
+
+from api.od import ODAPI
+from examples.petrinet import helpers
+from util.module_to_dict import module_to_dict
+
+def export_tapaal(state, m, mm):
+    loader = jinja2.FileSystemLoader(searchpath=THIS_DIR)
+    environment = jinja2.Environment(loader=loader)
+    template = environment.get_template("tapaal.jinja2")
+    return template.render({
+        'odapi': ODAPI(state, m, mm),
+        **globals()['__builtins__'],
+        **module_to_dict(helpers),
+    })

examples/petrinet/translational_semantics/tapaal/tapaal.jinja2

@@ -0,0 +1,52 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<pnml xmlns="http://www.informatik.hu-berlin.de/top/pnml/ptNetb">
+  <net active="true" id="PN" type="P/T net">
+
+  {% for i, (place_name, place) in enumerate(odapi.get_all_instances("PNPlace")) %}
+    <place id="{{ place_name }}"
+        name="{{ place_name }}"
+        initialMarking="{{ get_num_tokens(odapi, place) }}"
+        invariant="&lt; inf"
+        displayName="true"
+        nameOffsetX="0"
+        nameOffsetY="0"
+        positionX="{{ i * 100 + 100 }}"
+        positionY="100"
+    />
+  {% endfor %}
+
+  {% for i, (transition_name, transition) in enumerate(odapi.get_all_instances("PNTransition")) %}
+    <transition angle="0" displayName="true" id="{{ transition_name }}" infiniteServer="false" name="{{ transition_name }}" nameOffsetX="0" nameOffsetY="0" player="0" positionX="{{ i * 100 + 100 }}" positionY="300" priority="0" urgent="false"/>
+  {% endfor %}
+
+  {% for arc_name, arc in odapi.get_all_instances("arc") %}
+    <arc id="{{ arc_name }}"
+        inscription="{{ '[0,inf)' if odapi.get_type_name(odapi.get_source(arc)) == 'PNPlace' else '1' }}"
+        nameOffsetX="0"
+        nameOffsetY="0"
+        weight="1"
+        type="{{ 'timed' if odapi.get_type_name(odapi.get_source(arc)) == 'PNPlace' else 'normal' }}"
+        source="{{ odapi.get_name(odapi.get_source(arc)) }}"
+        target="{{ odapi.get_name(odapi.get_target(arc)) }}">
+      <arcpath arcPointType="false" id="0" xCoord="0" yCoord="0"/>
+      <arcpath arcPointType="false" id="1" xCoord="0" yCoord="0"/>
+    </arc>
+  {% endfor %}
+
+  {% for inh_arc_name, inh_arc in odapi.get_all_instances("inh_arc") %}
+    <arc id="{{ inh_arc_name }}"
+        inscription="[0,inf)"
+        nameOffsetX="0"
+        nameOffsetY="0"
+        type="tapnInhibitor"
+        weight="1"
+        source="{{ odapi.get_name(odapi.get_source(inh_arc)) }}"
+        target="{{ odapi.get_name(odapi.get_target(inh_arc)) }}">
+      <arcpath arcPointType="false" id="0" xCoord="0" yCoord="0"/>
+      <arcpath arcPointType="false" id="1" xCoord="0" yCoord="0"/>
+    </arc>
+  {% endfor %}
+
+  </net>
+  <feature isGame="false" isTimed="false"/>
+</pnml>

examples/semantics/operational/port/renderer.py

@@ -2,12 +2,14 @@ from concrete_syntax.common import indent
 from concrete_syntax.graphviz.make_url import make_url
 from examples.semantics.operational.port.helpers import design_to_state, state_to_design, get_time, get_num_ships
 
-def render_port_graphviz(od):
+def render_port_to_dot(od,
+    make_id=lambda name,obj: name # by default, we just use the object name for the graphviz node name
+):
     txt = ""
 
     def render_place(place):
         name = od.get_name(place)
-        return f'"{name}" [ label = "{name}\\n ships = {get_num_ships(od, place)}", style = filled, fillcolor = lightblue ]\n'
+        return f'"{make_id(name,place)}" [ label = "{name}\\n ships = {get_num_ships(od, place)}", style = filled, fillcolor = lightblue ]\n'
 
     for _, cap in od.get_all_instances("CapacityConstraint", include_subtypes=False):
         name = od.get_name(cap)
@@ -26,10 +28,10 @@ def render_port_graphviz(od):
     for _, berth_state in od.get_all_instances("BerthState", include_subtypes=False):
         berth = state_to_design(od, berth_state)
         name = od.get_name(berth)
-        txt += f'"{name}" [ label = "{name}\\n numShips = {get_num_ships(od, berth)}\\n status = {od.get_slot_value(berth_state, "status")}", fillcolor = yellow, style = filled]\n'
+        txt += f'"{make_id(name,berth)}" [ label = "{name}\\n numShips = {get_num_ships(od, berth)}\\n status = {od.get_slot_value(berth_state, "status")}", fillcolor = yellow, style = filled]\n'
 
     for _, gen in od.get_all_instances("Generator", include_subtypes=False):
-        txt += f'"{od.get_name(gen)}" [ label = "+", shape = diamond, fillcolor = green, fontsize = 30, style = filled ]\n'
+        txt += f'"{make_id(od.get_name(gen),gen)}" [ label = "+", shape = diamond, fillcolor = green, fontsize = 30, style = filled ]\n'
 
     for _, conn in od.get_all_instances("connection"):
         src = od.get_source(conn)
@@ -37,23 +39,26 @@ def render_port_graphviz(od):
         moved = od.get_slot_value(design_to_state(od, conn), "moved")
         src_name = od.get_name(src)
         tgt_name = od.get_name(tgt)
-        txt += f"{src_name} -> {tgt_name} [color=deepskyblue3, penwidth={1 if moved else 2}];\n"
+        txt += f"{make_id(src_name,src)} -> {make_id(tgt_name,tgt)} [color=deepskyblue3, penwidth={1 if moved else 2}];\n"
 
     for _, workers in od.get_all_instances("WorkerSet"):
         already_have = []
         name = od.get_name(workers)
         num_workers = od.get_slot_value(workers, "numWorkers")
-        txt += f'{name} [label="{num_workers} worker(s)", shape=parallelogram, fillcolor=chocolate, style=filled];\n'
+        txt += f'{make_id(name,workers)} [label="{num_workers} worker(s)", shape=parallelogram, fillcolor=chocolate, style=filled];\n'
         for lnk in od.get_outgoing(design_to_state(od, workers), "isOperating"):
             berth = od.get_target(lnk)
             already_have.append(berth)
-            txt += f"{name} -> {od.get_name(berth)} [arrowhead=none, color=chocolate];\n"
+            txt += f"{make_id(name,workers)} -> {make_id(od.get_name(berth),berth)} [arrowhead=none, color=chocolate];\n"
         for lnk in od.get_outgoing(workers, "canOperate"):
             berth = od.get_target(lnk)
             if berth not in already_have:
-                txt += f"{name} -> {od.get_name(berth)} [style=dotted, arrowhead=none, color=chocolate];\n"
+                txt += f"{make_id(name,workers)} -> {make_id(od.get_name(berth),berth)} [style=dotted, arrowhead=none, color=chocolate];\n"
 
-    return make_url(txt)
+    return txt
+
+def render_port_graphviz(od):
+    return make_url(render_port_to_dot(od))
 
 def render_port_textual(od):
     txt = ""

examples/semantics/translational/renderer.py

@@ -0,0 +1,90 @@
+from api.od import ODAPI
+from concrete_syntax.graphviz.renderer import render_object_diagram, make_graphviz_id
+from concrete_syntax.graphviz.make_url import show_graphviz
+from examples.petrinet.renderer import render_petri_net_to_dot
+from examples.semantics.operational.port.renderer import render_port_to_dot
+from examples.semantics.operational.port import helpers
+
+# COLORS
+PLACE_BG = "#DAE8FC" # fill color
+PLACE_FG = "#6C8EBF" # font, line, arrow
+BERTH_BG = "#FFF2CC"
+BERTH_FG = "#D6B656"
+CAPACITY_BG = "#F5F5F5"
+CAPACITY_FG = "#666666"
+WORKER_BG = "#D5E8D4"
+WORKER_FG = "#82B366"
+GENERATOR_BG = "#FFE6CC"
+GENERATOR_FG = "#D79B00"
+CLOCK_BG = "black"
+CLOCK_FG = "white"
+
+def graphviz_style_fg_bg(fg, bg):
+    return f"style=filled,fillcolor=\"{bg}\",color=\"{fg}\",fontcolor=\"{fg}\""
+
+def render_port(state, m, mm):
+    dot = render_object_diagram(state, m, mm,
+        reify=True,
+        only_render=[
+            # Only render these types
+            "Place", "Berth", "CapacityConstraint", "WorkerSet", "Generator", "Clock",
+            "connection", "capacityOf", "canOperate", "generic_link",
+            # Petri Net types not included (they are already rendered by other function)
+            # Port-State-types not included to avoid cluttering the diagram, but if you need them, feel free to add them.
+        ],
+        # We can style nodes/edges according to their type:
+        type_to_style={
+            "Place": graphviz_style_fg_bg(PLACE_FG, PLACE_BG),
+            "Berth": graphviz_style_fg_bg(BERTH_FG, BERTH_BG),
+            "CapacityConstraint": graphviz_style_fg_bg(CAPACITY_FG, CAPACITY_BG),
+            "WorkerSet": "shape=oval,"+graphviz_style_fg_bg(WORKER_FG, WORKER_BG),
+            "Generator": "shape=parallelogram,"+graphviz_style_fg_bg(GENERATOR_FG, GENERATOR_BG),
+            "Clock": graphviz_style_fg_bg(CLOCK_FG, CLOCK_BG),
+
+            # same blue as Place, thick line:
+            "connection": f"color=\"{PLACE_FG}\",fontcolor=\"{PLACE_FG}\",penwidth=2.0",
+
+            # same grey as CapacityConstraint
+            "capacityOf": f"color=\"{CAPACITY_FG}\",fontcolor=\"{CAPACITY_FG}\"",
+
+            # same green as WorkerSet
+            "canOperate": f"color=\"{WORKER_FG}\",fontcolor=\"{WORKER_FG}\"",
+
+            # purple line
+            "generic_link": "color=purple,fontcolor=purple,arrowhead=onormal",
+        },
+        # We have control over the node/edge labels that are rendered:
+        type_to_label={
+            "CapacityConstraint": lambda capconstr_name, capconstr, odapi: f"{capconstr_name}\\nshipCapacity={odapi.get_slot_value(capconstr, "shipCapacity")}",
+
+            "Place": lambda place_name, place, odapi: f"{place_name}\\nnumShips={helpers.get_num_ships(odapi, place)}",
+
+            "Berth": lambda berth_name, berth, odapi: f"{berth_name}\\nnumShips={helpers.get_num_ships(odapi, berth)}\\nstatus={odapi.get_slot_value(helpers.design_to_state(odapi, berth), "status")}",
+
+            "Clock": lambda _, clock, odapi: f"Clock\\ntime={odapi.get_slot_value(clock, "time")}",
+
+            "connection": lambda conn_name, conn, odapi: f"{conn_name}\\nmoved={odapi.get_slot_value(helpers.design_to_state(odapi, conn), "moved")}",
+
+            # hide generic link labels
+            "generic_link": lambda lnk_name, lnk, odapi: "",
+
+            "WorkerSet": lambda ws_name, ws, odapi: f"{ws_name}\\nnumWorkers={odapi.get_slot_value(ws, "numWorkers")}",
+
+            # hide the type (it's already clear enough)
+            "Generator": lambda gen_name, gen, odapi: gen_name,
+        },
+    )
+    return dot
+
+def render_port_and_petri_net(state, m, mm):
+    od = ODAPI(state, m, mm)
+    dot = ""
+    dot += "// petri net:\n"
+    dot += render_petri_net_to_dot(od)
+    dot += "\n// the rest:\n"
+    dot += render_port(state, m, mm)
+    return dot
+
+
+def show_port_and_petri_net(state, m, mm, engine="dot"):
+    show_graphviz(render_port_and_petri_net(state, m, mm), engine=engine)

examples/semantics/translational/runner_exec_pn.py

@@ -17,7 +17,7 @@ from examples.semantics.operational.simulator import Simulator, RandomDecisionMa
 from examples.semantics.operational.port import models
 from examples.semantics.operational.port.helpers import design_to_state, state_to_design, get_time
 from examples.semantics.operational.port.renderer import render_port_textual, render_port_graphviz
-from examples.petrinet.renderer import render_petri_net
+from examples.petrinet.renderer import show_petri_net
 from examples.semantics.operational import simulator
 
 import os
@@ -68,12 +68,15 @@ if __name__ == "__main__":
     matcher_rewriter = RuleMatcherRewriter(state, merged_mm, ramified_merged_mm)
     action_generator = ActionGenerator(matcher_rewriter, rules)
 
+    def render(od):
+        show_petri_net(od) # graphviz in web browser
+        return renderer.render_od(state, od.m, od.mm) # text in terminal
+
     sim = simulator.Simulator(
         action_generator=action_generator,
         decision_maker=simulator.InteractiveDecisionMaker(auto_proceed=False),
         # decision_maker=simulator.RandomDecisionMaker(seed=0),
-        renderer=lambda od: render_petri_net(od) + renderer.render_od(state, od.m, od.mm),
-        # renderer=lambda od: render_od(state, od.m, od.mm),
+        renderer=render,
     )
 
     sim.run(ODAPI(state, model, merged_mm))

examples/semantics/translational/runner_translate.py

@@ -5,18 +5,15 @@ from concrete_syntax.plantuml.renderer import render_object_diagram, render_clas
 from concrete_syntax.plantuml.make_url import make_url
 from api.od import ODAPI
 
-from transformation.ramify import ramify
-from transformation.topify.topify import Topifier
-from transformation.merger import merge_models
 from transformation.ramify import ramify
 from transformation.rule import RuleMatcherRewriter
 
 from util import loader
+from util.module_to_dict import module_to_dict
 
-from examples.semantics.operational.simulator import Simulator, RandomDecisionMaker, InteractiveDecisionMaker
-from examples.semantics.operational.port import models
-from examples.semantics.operational.port.helpers import design_to_state, state_to_design, get_time
+from examples.semantics.operational.port import models, helpers
 from examples.semantics.operational.port.renderer import render_port_textual, render_port_graphviz
+from examples.semantics.translational.renderer import show_port_and_petri_net
 from examples.petrinet.renderer import render_petri_net
 
 import os
@@ -76,7 +73,14 @@ if __name__ == "__main__":
     print('ready!')
 
     port_m_rt = port_m_rt_initial
-    matcher_rewriter = RuleMatcherRewriter(state, merged_mm, ramified_merged_mm)
+    eval_context = {
+        # make all the functions defined in 'helpers' module available to 'condition'-code in LHS/NAC/RHS:
+        **module_to_dict(helpers),
+        # another example: in all 'condition'-code, there will be a global variable 'meaning_of_life', equal to 42:
+        'meaning_of_life': 42, # just to demonstrate - feel free to remove this
+    }
+    print('The following additional globals are available:', ', '.join(list(eval_context.keys())))
+    matcher_rewriter = RuleMatcherRewriter(state, merged_mm, ramified_merged_mm, eval_context=eval_context)
 
     ###################################
     # Because the matching of many different rules can be slow,
@@ -104,7 +108,7 @@ if __name__ == "__main__":
         try:
             with open(filename, "r") as file:
                 port_m_rt = parser.parse_od(state, file.read(), merged_mm)
-                print('loaded', filename)
+            print(f'skip rule (found {filename})')
         except FileNotFoundError:
             # Fire every rule until it cannot match any longer:
             while True:
@@ -123,6 +127,12 @@ if __name__ == "__main__":
                 print('wrote', filename)
                 render_petri_net(ODAPI(state, port_m_rt, merged_mm))
 
+                # Uncomment to show also the port model:
+                # show_port_and_petri_net(state, port_m_rt, merged_mm)
+
+                # Uncomment to pause after each rendering:
+                # input()
+
     ###################################
     # Once you have generated a Petri Net, you can execute the petri net:
     #

requirements.txt

@@ -1 +1,2 @@
 lark==1.1.9
+jinja2==3.1.4

transformation/matcher.py

@@ -168,7 +168,14 @@ def _cannot_call_matched(_):
 
 # This function returns a Generator of matches.
 # The idea is that the user can iterate over the match set, lazily generating it: if only interested in the first match, the entire match set doesn't have to be generated.
-def match_od(state, host_m, host_mm, pattern_m, pattern_mm, pivot={}):
+def match_od(state,
+    host_m, # the host graph, in which to search for matches
+    host_mm, # meta-model of the host graph
+    pattern_m, # the pattern to look for
+    pattern_mm, # the meta-model of the pattern (typically the RAMified version of host_mm)
+    pivot={}, # optional: a partial match (restricts possible matches, and speeds up the match process)
+    eval_context={}, # optional: additional variables, functions, ... to be available while evaluating condition-code in the pattern. Will be available as global variables in the condition-code.
+):
     bottom = Bottom(state)
 
     # compute subtype relations and such:
@@ -177,6 +184,21 @@ def match_od(state, host_m, host_mm, pattern_m, pattern_mm, pivot={}):
     pattern_odapi = ODAPI(state, pattern_m, pattern_mm)
     pattern_mm_odapi = ODAPI(state, pattern_mm, cdapi.mm)
 
+    # 'globals'-dict used when eval'ing conditions
+    bound_api = bind_api_readonly(odapi)
+    builtin = {
+        **bound_api,
+        'matched': _cannot_call_matched,
+        'odapi': odapi,
+    }
+    for key in eval_context:
+        if key in builtin:
+            print(f"WARNING: custom global '{key}' overrides pre-defined API function. Consider renaming it.")
+    eval_globals = {
+        **builtin,
+        **eval_context,
+    }
+
     # Function object for pattern matching. Decides whether to match host and guest vertices, where guest is a RAMified instance (e.g., the attributes are all strings with Python expressions), and the host is an instance (=object diagram) of the original model (=class diagram)
     class RAMCompare:
         def __init__(self, bottom, host_od):
@@ -234,10 +256,7 @@ def match_od(state, host_m, host_mm, pattern_m, pattern_mm, pivot={}):
                     #   - incompatible slots may be matched (it is only when their AttributeLinks are matched, that we know the types will be compatible)
                     with Timer(f'EVAL condition {g_vtx.name}'):
                         ok = exec_then_eval(python_code,
-                            _globals={
-                                **bind_api_readonly(odapi),
-                                'matched': _cannot_call_matched,
-                            },
+                            _globals=eval_globals,
                             _locals={'this': h_vtx.node_id})
                     self.conditions_to_check.pop(g_vtx.name, None)
                     return ok
@@ -324,13 +343,14 @@ def match_od(state, host_m, host_mm, pattern_m, pattern_mm, pivot={}):
 
 
     def check_conditions(name_mapping):
+        eval_globals = {
+            **bound_api,
+            # this time, the real 'matched'-function can be used:
+            'matched': lambda name: bottom.read_outgoing_elements(host_m, name_mapping[name])[0],
+            **eval_context,
+        }
         def check(python_code: str, loc):
-            return exec_then_eval(python_code,
-                _globals={
-                    **bind_api_readonly(odapi),
-                    'matched': lambda name: bottom.read_outgoing_elements(host_m, name_mapping[name])[0],
-                },
-                _locals=loc)
+            return exec_then_eval(python_code, _globals=eval_globals, _locals=loc)
 
         # Attribute conditions
         for pattern_name, host_name in name_mapping.items():

transformation/rewriter.py

@@ -3,6 +3,7 @@
 #   - Change attribute values
 #   - ? that's it?
 
+import re
 from uuid import UUID
 from api.od import ODAPI, bind_api
 from services.bottom.V0 import Bottom
@@ -13,12 +14,22 @@ from services.primitives.actioncode_type import ActionCode
 from services.primitives.integer_type import Integer
 from util.eval import exec_then_eval, simply_exec
 
+identifier_regex_pattern = '[_A-Za-z][._A-Za-z0-9]*'
+identifier_regex = re.compile(identifier_regex_pattern)
 
 class TryAgainNextRound(Exception):
     pass
 
 # Rewrite is performed in-place (modifying `host_m`)
-def rewrite(state, lhs_m: UUID, rhs_m: UUID, pattern_mm: UUID, lhs_match: dict, host_m: UUID, host_mm: UUID):
+def rewrite(state,
+    lhs_m: UUID, # LHS-pattern
+    rhs_m: UUID, # RHS-pattern
+    pattern_mm: UUID, # meta-model of both patterns (typically the RAMified host_mm)
+    lhs_match: dict, # a match, morphism, from lhs_m to host_m (mapping pattern name -> host name), typically found by the 'match_od'-function.
+    host_m: UUID, # host model
+    host_mm: UUID, # host meta-model
+    eval_context={}, # optional: additional variables/functions to be available while executing condition-code. These will be seen as global variables.
+):
     bottom = Bottom(state)
 
     # Need to come up with a new, unique name when creating new element in host-model:
@@ -74,6 +85,29 @@ def rewrite(state, lhs_m: UUID, rhs_m: UUID, pattern_mm: UUID, lhs_match: dict,
     # to be grown
     rhs_match = { name : lhs_match[name] for name in common }
 
+
+    bound_api = bind_api(host_odapi)
+    original_delete = bound_api["delete"]
+    def wrapped_delete(obj):
+        not_allowed_to_delete = { host_odapi.get(host_name): pattern_name  for pattern_name, host_name in rhs_match.items() }
+        if obj in not_allowed_to_delete:
+            pattern_name = not_allowed_to_delete[obj]
+            raise Exception(f"\n\nYou're trying to delete the element that was matched with the RHS-element '{pattern_name}'. This is not allowed! You're allowed to delete anything BUT NOT elements matched with your RHS-pattern. Instead, simply remove the element '{pattern_name}' from your RHS, if you want to delete it.")
+        return original_delete(obj)
+    bound_api["delete"] = wrapped_delete
+    builtin = {
+        **bound_api,
+        'matched': matched_callback,
+        'odapi': host_odapi,
+    }
+    for key in eval_context:
+        if key in builtin:
+            print(f"WARNING: custom global '{key}' overrides pre-defined API function. Consider renaming it.")
+    eval_globals = {
+        **builtin,
+        **eval_context,
+    }
+
     # 1. Perform creations - in the right order!
     remaining_to_create = list(to_create)
     while len(remaining_to_create) > 0:
@@ -86,11 +120,9 @@ def rewrite(state, lhs_m: UUID, rhs_m: UUID, pattern_mm: UUID, lhs_match: dict,
                 name_expr = rhs_odapi.get_slot_value(rhs_obj, "name")
             except:
                 name_expr = f'"{rhs_name}"' # <- if the 'name' slot doesnt exist, use the pattern element name
-            suggested_name = exec_then_eval(name_expr,
-                _globals={
-                    **bind_api(host_odapi),
-                    'matched': matched_callback,
-                })
+            suggested_name = exec_then_eval(name_expr, _globals=eval_globals)
+            if not identifier_regex.match(suggested_name):
+                raise Exception(f"In the RHS pattern element '{rhs_name}', the following name-expression:\n  {name_expr}\nproduced the name:\n  '{suggested_name}'\nwhich contains illegal characters.\nNames should match the following regex: {identifier_regex_pattern}")
             rhs_type = rhs_odapi.get_type(rhs_obj)
             host_type = ramify.get_original_type(bottom, rhs_type)
             # for debugging:
@@ -157,10 +189,7 @@ def rewrite(state, lhs_m: UUID, rhs_m: UUID, pattern_mm: UUID, lhs_match: dict,
                     host_attr_name = host_mm_odapi.get_slot_value(host_attr_link, "name")
                     val_name = f"{host_src_name}.{host_attr_name}"
                     python_expr = ActionCode(UUID(bottom.read_value(rhs_obj)), bottom.state).read()
-                    result = exec_then_eval(python_expr, _globals={
-                        **bind_api(host_odapi),
-                        'matched': matched_callback,
-                    })
+                    result = exec_then_eval(python_expr, _globals=eval_globals)
                     host_odapi.create_primitive_value(val_name, result, is_code=False)
                     rhs_match[rhs_name] = val_name
                 else:
@@ -192,10 +221,7 @@ def rewrite(state, lhs_m: UUID, rhs_m: UUID, pattern_mm: UUID, lhs_match: dict,
             rhs_obj = rhs_odapi.get(common_name)
             python_expr = ActionCode(UUID(bottom.read_value(rhs_obj)), bottom.state).read()
             result = exec_then_eval(python_expr,
-                _globals={
-                    **bind_api(host_odapi),
-                    'matched': matched_callback,
-                },
+                _globals=eval_globals,
                 _locals={'this': host_obj}) # 'this' can be used to read the previous value of the slot
             host_odapi.overwrite_primitive_value(host_obj_name, result, is_code=False)
         else:
@@ -235,18 +261,12 @@ def rewrite(state, lhs_m: UUID, rhs_m: UUID, pattern_mm: UUID, lhs_match: dict,
             # rhs_obj is an object or link (because association is subtype of class)
             python_code = rhs_odapi.get_slot_value_default(rhs_obj, "condition", default="")
             simply_exec(python_code,
-                _globals={
-                    **bind_api(host_odapi),
-                    'matched': matched_callback,
-                },
+                _globals=eval_globals,
                 _locals={'this': host_obj})
 
     # 5. Execute global actions
     for cond_name, cond in rhs_odapi.get_all_instances("GlobalCondition"):
         python_code = rhs_odapi.get_slot_value(cond, "condition")
-        simply_exec(python_code, _globals={
-            **bind_api(host_odapi),
-            'matched': matched_callback,
-        })
+        simply_exec(python_code, _globals=eval_globals)
 
     return rhs_match

transformation/rule.py

@@ -26,10 +26,11 @@ class _NAC_MATCHED(Exception):
 
 # Helper for executing NAC/LHS/RHS-type rules
 class RuleMatcherRewriter:
-    def __init__(self, state, mm: UUID, mm_ramified: UUID):
+    def __init__(self, state, mm: UUID, mm_ramified: UUID, eval_context={}):
         self.state = state
         self.mm = mm
         self.mm_ramified = mm_ramified
+        self.eval_context = eval_context
 
     # Generates matches.
     # Every match is a dictionary with entries LHS_element_name -> model_element_name
@@ -38,7 +39,9 @@ class RuleMatcherRewriter:
             host_m=m,
             host_mm=self.mm,
             pattern_m=lhs,
-            pattern_mm=self.mm_ramified)
+            pattern_mm=self.mm_ramified,
+            eval_context=self.eval_context,
+        )
 
         try:
             # First we iterate over LHS-matches:
@@ -64,7 +67,9 @@ class RuleMatcherRewriter:
                                     host_mm=self.mm,
                                     pattern_m=nac,
                                     pattern_mm=self.mm_ramified,
-                                    pivot=lhs_match) # try to "grow" LHS-match with NAC-match
+                                    pivot=lhs_match, # try to "grow" LHS-match with NAC-match
+                                    eval_context=self.eval_context,
+                                )
 
                                 try:
                                     # for nac_match in nac_matcher:
@@ -117,7 +122,9 @@ class RuleMatcherRewriter:
                 pattern_mm=self.mm_ramified,
                 lhs_match=lhs_match,
                 host_m=cloned_m,
-                host_mm=self.mm)
+                host_mm=self.mm,
+                eval_context=self.eval_context,
+            )
         except Exception as e:
             # Make exceptions raised in eval'ed code easier to trace:
             e.add_note(f"while executing RHS of '{rule_name}'")

util/loader.py

@@ -5,13 +5,14 @@ from concrete_syntax.common import indent
 from transformation.rule import Rule
 
 # parse model and check conformance
-def parse_and_check(state, m_cs, mm, descr: str, check_conformance=True, type_transform=lambda type_name: type_name):
+def parse_and_check(state, m_cs, mm, descr: str, check_conformance=True, type_transform=lambda type_name: type_name, name_generator=parser.DefaultNameGenerator()):
     try:
         m = parser.parse_od(
             state,
             m_text=m_cs,
             mm=mm,
             type_transform=type_transform,
+            name_generator=name_generator,
         )
     except Exception as e:
         e.add_note("While parsing model " + descr)
@@ -35,6 +36,11 @@ def read_file(filename):
 
 KINDS = ["nac", "lhs", "rhs"]
 
+# Phony name generator that raises an error if you try to use it :)
+class LHSNameGenerator:
+    def __call__(self, type_name):
+        raise Exception(f"Error: Object or link of type '{type_name}' does not have a name.\nAnonymous objects/links are not allowed in the LHS of a rule, because they can have unintended consequences. Please give all of the elements in the LHS explicit names.")
+
 # load model transformation rules
 def load_rules(state, get_filename, rt_mm_ramified, rule_names, check_conformance=True):
     rules = {}
@@ -62,9 +68,12 @@ def load_rules(state, get_filename, rt_mm_ramified, rule_names, check_conformanc
                     if suffix == "":
                         print(f"Warning: rule {rule_name} has no NAC ({filename} not found)")
                 return nacs
-            elif kind == "lhs" or kind == "rhs":
+            else:
                 try:
-                    m = parse_and_check(state, read_file(filename), rt_mm_ramified, descr, check_conformance)
+                    if kind == "lhs":
+                        m = parse_and_check(state, read_file(filename), rt_mm_ramified, descr, check_conformance, name_generator=LHSNameGenerator())
+                    elif kind == "rhs":
+                        m = parse_and_check(state, read_file(filename), rt_mm_ramified, descr, check_conformance)
                     files_read.append(filename)
                     return m
                 except FileNotFoundError as e:

util/module_to_dict.py

@@ -0,0 +1,8 @@
+# Based on: https://stackoverflow.com/a/46263657
+def module_to_dict(module):
+    context = {}
+    for name in dir(module):
+        # this will filter out 'private' functions, as well as __builtins__, __name__, __package__, etc.:
+        if not name.startswith('_'):
+            context[name] = getattr(module, name)
+    return context