add comparison functions for SetIterator and DictIterator

lib/compare/dynamic.js

@@ -1,10 +1,12 @@
 import { getInst, getType } from "../primitives/dynamic.js";
 import { SymbolBool, SymbolBottom, SymbolByte, SymbolChar, SymbolDouble, SymbolDynamic, SymbolInt, SymbolUUID, SymbolType, SymbolUnit, SymbolOrdering } from "../primitives/primitive_types.js";
 import { UNBOUND_SYMBOLS } from "../primitives/typevars.js";
+import { symbolDictIterator } from "../structures/dict.types.js";
+import { symbolSetIterator } from "../structures/set.types.js";
 import { symbolDict, symbolFunction, symbolList, symbolProduct, symbolSet, symbolSum } from "../structures/type_constructors.js";
 import { prettyT } from "../util/pretty.js";
 import { compareBools, compareDoubles, compareOrderings, compareStrings, compareSymbols, compareUnits } from "./primitives.js";
-import { compareDicts, compareFunctions, compareLists, compareProducts, compareSets, compareSums } from "./structures.js";
+import { compareDictIterators, compareDicts, compareFunctions, compareLists, compareProducts, compareSetIterators, compareSets, compareSums } from "./structures.js";
 import { compareTypes } from "./type.js";
 
 export const compareDynamic = x => y =>
@@ -28,12 +30,14 @@ const typeSymbolToCmp = new Map([
   [SymbolOrdering, compareOrderings],
 
   // these functions take extra comparison callbacks:
-  [symbolFunction, compareFunctions],
-  [symbolSum     , compareSums     ],
-  [symbolProduct , compareProducts ],
-  [symbolList    , compareLists    ],
-  [symbolSet     , compareSets     ],
-  [symbolDict    , compareDicts    ],
+  [symbolFunction    , compareFunctions    ],
+  [symbolSum         , compareSums         ],
+  [symbolProduct     , compareProducts     ],
+  [symbolList        , compareLists        ],
+  [symbolSet         , compareSets         ],
+  [symbolDict        , compareDicts        ],
+  [symbolSetIterator , compareSetIterators ],
+  [symbolDictIterator, compareDictIterators],
 
   // even though we cannot compare typevar instances,
   // we still need to give a function or shit will break

lib/compare/structures.js

@@ -1,6 +1,6 @@
 // Total ordering of composed types
 
-import { compareDoubles, compareStrings } from "./primitives.js"
+import { compareBools, compareDoubles, compareStrings } from "./primitives.js"
 import { get, length as lengthLs } from "../structures/list.js";
 import { read as readSet, length as lengthSet, first as firstSet } from "../structures/set.js";
 import { read as readDict, length as lengthDict, first as firstDict } from "../structures/dict.js";
@@ -93,3 +93,40 @@ export const compareDicts = compareKeys => compareValues => x => y => {
       return iterate(firstDict(x))(firstDict(y));
     })();
 };
+
+export const compareSetIterators = compareElems => x => y => {
+  // first compare the sets the iterators belong to,
+  // if the iterators belong to different sets, then they surely are not equal:
+  const ord = compareSets(compareElems)(x.tree)(y.tree);
+  if (ord !== 0) {
+    return ord; // sets differ
+  }
+  // sets are equal...
+  const xIsValid = x !== undefined && x.valid;
+  const yIsValid = y !== undefined && y.valid;
+  const ord2 = compareBools(xIsValid)(yIsValid);
+  if (ord2 !== 0) {
+    return ord2; // one is valid, the other is not
+  }
+  // both iterators are valid...
+  return compareElems(x.key)(y.key);
+};
+
+export const compareDictIterators = compareKeys => compareValues => x => y => {
+  // first compare the sets the iterators belong to,
+  // if the iterators belong to different sets, then they surely are not equal:
+  const ord = compareDicts(compareKeys)(compareValues)(x.tree)(y.tree);
+  if (ord !== 0) {
+    return ord; // sets differ
+  }
+  // sets are equal...
+  const xIsValid = x !== undefined && x.valid;
+  const yIsValid = y !== undefined && y.valid;
+  const ord2 = compareBools(xIsValid)(yIsValid);
+  if (ord2 !== 0) {
+    return ord2; // one is valid, the other is not
+  }
+  // both iterators are valid...
+  return compareKeys  (x.key  )(y.key  )
+      || compareValues(x.value)(y.value)
+};