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* Every real language has a `map' function.
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@ -221,7 +221,7 @@ Expr evalExpr2(EvalState & state, Expr e)
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(state, args2);
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} else
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/* Need more arguments, so propagate the primop. */
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return ATmake("PrimOp(<int>, <term>, <list>)",
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return ATmake("PrimOp(<int>, <term>, <term>)",
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arity, fun, args);
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}
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@ -314,8 +314,23 @@ Expr primIsNull(EvalState & state, const ATermVector & args)
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/* Apply a function to every element of a list. */
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Expr primMap(EvalState & state, Expr fun, Expr list)
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Expr primMap(EvalState & state, const ATermVector & args)
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{
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Expr fun = evalExpr(state, args[0]);
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Expr list = evalExpr(state, args[1]);
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ATMatcher m;
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ATermList list2;
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if (!(atMatch(m, list) >> "List" >> list2))
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throw Error("`map' expects a list as its second argument");
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ATermList list3 = ATempty;
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for (ATermIterator i(list2); i; ++i)
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list3 = ATinsert(list3,
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ATmake("Call(<term>, <term>)", fun, *i));
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return ATmake("List(<term>)", ATreverse(list3));
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}
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@ -330,4 +345,6 @@ void EvalState::addPrimOps()
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addPrimOp("baseNameOf", 1, primBaseNameOf);
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addPrimOp("toString", 1, primToString);
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addPrimOp("isNull", 1, primIsNull);
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addPrimOp("map", 2, primMap);
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}
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