fixes #2599

compiler/semfold.nim

@@ -430,17 +430,10 @@ proc evalOp(m: TMagic, n, a, b, c: PNode): PNode =
   of mCompileOptionArg:
     result = newIntNodeT(ord(
       testCompileOptionArg(getStr(a), getStr(b), n.info)), n)
-  of mNewString, mNewStringOfCap,
-     mExit, mInc, ast.mDec, mEcho, mSwap, mAppendStrCh,
-     mAppendStrStr, mAppendSeqElem, mSetLengthStr, mSetLengthSeq,
-     mParseExprToAst, mParseStmtToAst, mExpandToAst, mTypeTrait, mDotDot,
-     mNLen..mNError, mEqRef, mSlurp, mStaticExec, mNGenSym, mSpawn,
-     mParallel, mPlugin, mGetTypeInfo, mTypeOf:
-    discard
   of mEqProc:
     result = newIntNodeT(ord(
         exprStructuralEquivalent(a, b, strictSymEquality=true)), n)
-  else: internalError(a.info, "evalOp(" & $m & ')')
+  else: discard
 
 proc getConstIfExpr(c: PSym, n: PNode): PNode =
   result = nil

compiler/sigmatch.nim

@@ -265,9 +265,6 @@ proc describeArgs*(c: PContext, n: PNode, startIdx = 1;
 
 proc typeRel*(c: var TCandidate, f, aOrig: PType, doBind = true): TTypeRelation
 proc concreteType(c: TCandidate, t: PType): PType =
-  # currently `[]=` is defined rather sloppily in system.nim, so we have
-  # a special type matching rule for it:
-  if c.calleeSym != nil and c.calleeSym.magic == mArrPut: return t
   case t.kind
   of tyArrayConstr:
     # make it an array
@@ -1694,7 +1691,7 @@ proc partialMatch*(c: PContext, n, nOrig: PNode, m: var TCandidate) =
   matchesAux(c, n, nOrig, m, marker)
 
 proc matches*(c: PContext, n, nOrig: PNode, m: var TCandidate) =
-  if m.calleeSym != nil and m.calleeSym.magic == mArrGet:
+  if m.calleeSym != nil and m.calleeSym.magic in {mArrGet, mArrPut}:
     m.state = csMatch
     m.call = n
     return