make experimental feature for now

compiler/nim.cfg

@@ -60,3 +60,7 @@ define:useStdoutAsStdmsg
 @if nimHasVtables:
   experimental:vtables
 @end
+
+@if nimHasTypeBoundOps:
+  experimental:typeBoundOps
+@end

compiler/options.nim

@@ -229,6 +229,7 @@ type
     # alternative to above:
     genericsOpenSym
     vtables
+    typeBoundOps
 
   LegacyFeature* = enum
     allowSemcheckedAstModification,

compiler/semcall.nim

@@ -64,15 +64,17 @@ proc initCandidateSymbols(c: PContext, headSymbol: PNode,
           result.add((paramTyp.n.sym, o.lastOverloadScope))
 
     symx = nextOverloadIter(o, c, headSymbol)
-  if headSymbol.kind != nkDotExpr: # qualified, maybe whitelist ident/opensymchoice?
-    # add all type bound ops with this specific name
-    # may be slow to do this for every single call, but the nominal types
-    # imply a straightforward match
-    let name = considerQuotedIdent(c, headSymbol)
-    for boundOp in c.graph.typeBoundOps.getOrDefault(name, @[]):
-      if boundOp.id notin symMarker:
-        # no need to add to symMarker, type bound ops should be unique already
-        result.add((boundOp, -2))
+  if typeBoundOps in c.features:
+    # TODO move this to happen after `prepareOperand` and per type
+    if headSymbol.kind != nkDotExpr: # qualified, maybe whitelist ident/opensymchoice?
+      # add all type bound ops with this specific name
+      # may be slow to do this for every single call, but the nominal types
+      # imply a straightforward match
+      let name = considerQuotedIdent(c, headSymbol)
+      for boundOp in c.graph.typeBoundOps.getOrDefault(name, @[]):
+        if boundOp.id notin symMarker:
+          # no need to add to symMarker, type bound ops should be unique already
+          result.add((boundOp, -2))
   if result.len > 0:
     best = initCandidate(c, result[0].s, initialBinding,
                   result[0].scope, diagnostics)

tests/config.nims

@@ -43,3 +43,4 @@ when not defined(testsConciseTypeMismatch):
   switch("legacy", "verboseTypeMismatch")
 switch("experimental", "vtables")
 switch("experimental", "openSym")
+switch("experimental", "typeBoundOps")