From b277ae88b653f039b576717f8d9ecd56e5dbd2fe Mon Sep 17 00:00:00 2001
From: Toine Hartman <toine.hartman@swat.engineering>
Date: Wed, 19 Aug 2026 11:29:09 +0200
Subject: [PATCH 1/2] Reapply "Merge branch 'main' into
 fix/logicallocs-in-compiler"

This reverts commit 3d5369b35a00bddc085d722010baf329580b1c68.
---
 .git-blame-ignore-revs                        |   8 +-
 .settings/org.eclipse.core.resources.prefs    |   1 +
 pom.xml                                       |   9 +-
 .../agrammar/definition/Symbols.rsc           |  10 ++
 .../lang/rascalcore/check/ATypeUtils.rsc      |  21 ++-
 .../lang/rascalcore/check/Checker.rsc         |   2 +-
 .../check/CollectDataDeclaration.rsc          |   8 +-
 .../rascalcore/check/CollectDeclaration.rsc   |  16 +--
 .../lang/rascalcore/check/CollectLiteral.rsc  |   2 +-
 .../rascalcore/check/CollectOperators.rsc     |   2 +-
 .../lang/rascalcore/check/CollectPattern.rsc  |  20 +--
 .../rascalcore/check/CollectStatement.rsc     |  26 ++--
 .../check/CollectSyntaxDeclaration.rsc        |   4 +-
 .../lang/rascalcore/check/CollectType.rsc     |   8 +-
 .../compiler/lang/rascalcore/check/Import.rsc |   4 +-
 .../check/tests/StaticTestingUtils.rsc        |   4 +-
 .../rascalcore/check/tests/UseDefTests.rsc    |   6 +
 .../lang/rascalcore/compile/Examples/A.rsc    |   6 +-
 .../rascalmpl/library/util/Reflective.java    |   3 +
 .../rascalmpl/uri/URIResolverRegistry.java    |   7 +-
 src/org/rascalmpl/uri/URIUtil.java            |   4 -
 src/org/rascalmpl/uri/resolvers.config        |   2 +
 .../uri/unsupported/LibraryURIResolver.java   |   7 +
 .../uri/unsupported/UnknownURIResolver.java   |   9 ++
 .../unsupported/UnsupportedURIResolver.java   | 125 ++++++++++++++++++
 .../rascalmpl/test/repl/JlineParserTest.java  |   2 +-
 26 files changed, 246 insertions(+), 70 deletions(-)
 create mode 100644 src/org/rascalmpl/uri/unsupported/LibraryURIResolver.java
 create mode 100644 src/org/rascalmpl/uri/unsupported/UnknownURIResolver.java
 create mode 100644 src/org/rascalmpl/uri/unsupported/UnsupportedURIResolver.java

diff --git a/.git-blame-ignore-revs b/.git-blame-ignore-revs
index 933e3bb46e1..64c543262bf 100644
--- a/.git-blame-ignore-revs
+++ b/.git-blame-ignore-revs
@@ -4,9 +4,9 @@
 # git config blame.ignoreRevsFile .git-blame-ignore-revs
 
 # indent fix for JSON
-31b1031ade5d84f9c60e30d17da3b55e78d291fb
+f5d0490e283e36e527821736b11f9b09163b67b6
 
 # fixing tabs & spaces mixed
-0d048e15683740b5c944be5333ec0680df825e47
-23ec4b622bbe503ef013be5a458e45ae6fd89b97
-200b0352084be9435c64aa60c550edd24a59131b
+1b9801104c0e839e229c25f6a16b72a48e874594
+97fc3b0739f848c8277f2b2c2aae3530afff37a6
+a004c2604cef592975f60a572c4a03491b2f7971
diff --git a/.settings/org.eclipse.core.resources.prefs b/.settings/org.eclipse.core.resources.prefs
index 1d4bcb41c23..e16014115e1 100644
--- a/.settings/org.eclipse.core.resources.prefs
+++ b/.settings/org.eclipse.core.resources.prefs
@@ -5,6 +5,7 @@ encoding//src/org/rascalmpl/library/experiments/vis2/lib/nv.d3.css=UTF-8
 encoding//src/org/rascalmpl/library/experiments/vis2/lib/nv.d3.js=UTF-8
 encoding//src/org/rascalmpl/library/experiments/vis2/lib/reset.css=UTF-8
 encoding//src/org/rascalmpl/library/lang/rascal/tests/functionality/DataType.rsc=UTF-8
+encoding//target/generated-resources=UTF-8
 encoding//test/org/rascalmpl/test/data=UTF-8
 encoding/<project>=UTF-8
 encoding/META-INF=UTF-8
diff --git a/pom.xml b/pom.xml
index 8d6c46478bb..82073b97177 100644
--- a/pom.xml
+++ b/pom.xml
@@ -58,12 +58,9 @@
                 </excludes>
             </resource>
             <resource>
-                <directory>.</directory>
+                <directory>META-INF</directory>
+                <targetPath>${project.build.outputDirectory}/META-INF</targetPath>  <!-- this way of framing it works around issue in m2e -->
                 <filtering>false</filtering>
-                <includes>
-                    <include>META-INF/RASCAL.MF</include>
-                    <include>rascal-DEPENDENCIES.txt</include>
-                </includes>
             </resource>
             <resource>
                 <directory>${project.build.directory}/generated-resources</directory>
@@ -288,7 +285,7 @@
                         </goals>
                         <phase>package</phase>
                         <configuration>
-                            <output>rascal-DEPENDENCIES.txt</output>
+                            <output>${project.build.outputDirectory}/rascal-DEPENDENCIES.txt</output>
                         </configuration>
                     </execution>
                 </executions>
diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/agrammar/definition/Symbols.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/agrammar/definition/Symbols.rsc
index a07a75ae2e3..ebd0d32a38c 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/agrammar/definition/Symbols.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/agrammar/definition/Symbols.rsc
@@ -133,6 +133,16 @@ public AType defsym2AType(Sym sym, SyntaxRole sr) {
   }
 }
 
+public Tree defsym2IdTree(Sym sym) = top-down-break visit (sym) {
+  case lang::rascal::\syntax::Rascal::nonterminal(Nonterminal n): return n;
+  case \parametrized(Nonterminal n, _): return n;
+  case \start(Nonterminal n): return n;
+  default: {
+    iprintln(sym);
+    throw "defsym2IdTree, missed a case <sym>";
+  }
+};
+
 public list[AType] args2ATypes(Sym* args) {
   return [sym2AType(s) | Sym s <- args];
 }
diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/check/ATypeUtils.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/check/ATypeUtils.rsc
index 4243ece11cc..697640d2347 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/check/ATypeUtils.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/check/ATypeUtils.rsc
@@ -71,6 +71,7 @@ str prettyAType(avalue()) = "value";
 str prettyAType(aloc()) = "loc";
 str prettyAType(adatetime()) = "datetime";
 str prettyAType(alist(AType t)) = "list[<prettyAType(t)>]";
+str prettyAType(abag(AType t)) = "bag[<prettyAType(t)>]";
 str prettyAType(aset(AType t)) = "set[<prettyAType(t)>]";
 str prettyAType(atuple(AType ts)) = "tuple[<prettyAType(ts)>]";
 str prettyAType(amap(AType d, AType r)) = "map[<prettyAType(d)>, <prettyAType(r)>]";
@@ -92,6 +93,7 @@ str prettyAType(t: acons(AType adt, /*str consName,*/
                 list[AType] fields,
                 list[Keyword] kwFields))
                  = "<prettyAType(adt)>::<t.alabel>(<intercalate(", ", ["<prettyAType(ft)><ft.alabel? ? " <ft.alabel>" : "">" | ft <- fields])><isEmpty(kwFields) ? "" : ", "><intercalate(",", ["<prettyAType(kw.fieldType)> <kw.fieldName>=..." | Keyword kw <- kwFields])>)";
+str prettyAType(aprod(AProduction production)) = prettyAType(production);
 
 str prettyAType(amodule(str mname)) = "module <mname>";         
 str prettyAType(aparameter(str pn, AType t, closed=c)) =
@@ -108,7 +110,12 @@ str prettyAType(Keyword kw: kwField(fieldType, fieldName, _,defaultExp)) = "<pre
 str prettyAType(Keyword kw: kwField(fieldType,fieldName, _)) = "<prettyAType(fieldType) <kw.fieldName> = ?";
 
 // non-terminal symbols
-str prettyAType(\prod(AType s, list[AType] fs/*, SyntaxRole _*/)) = "<prettyAType(s)> : (<intercalate(", ", [ prettyAType(f) | f <- fs ])>)"; //TODO others
+str prettyAType(\prod(AType s, list[AType] fs/*, SyntaxRole _*/)) = "<prettyAType(s)> : <intercalate(" ", [ prettyAType(f) | f <- fs ])>";
+str prettyAType(regular(AType s)) = prettyAType(s);
+str prettyAType(priority(AType _s, list[AProduction] choices)) = "<intercalate(" \> ", [ prettyAType(a) | a <- choices ])>";
+str prettyAType(associativity(AType _s, AAssociativity \assoc, set[AProduction] alternatives)) = "<prettyAssoc(\assoc)> ( <intercalate(" | ", [ prettyAType(a) | a <- alternatives ])> )";
+str prettyAType(reference(AType s, str cons)) = ":<cons>";
+str prettyAType(\achoice(AType s, set[AProduction] alternatives)) = "<intercalate(" | ", [ prettyAType(a) | a <- alternatives ])>";
 
 // terminal symbols
 str prettyAType(alit(str string)) = string;
@@ -124,9 +131,9 @@ str prettyAType(\aempty()) = "()";
 str prettyAType(\opt(AType symbol)) = "<prettyAType(symbol)>?";
 str prettyAType(\iter(AType symbol)) = "<prettyAType(symbol)>+";
 str prettyAType(\iter-star(AType symbol)) = "<prettyAType(symbol)>*";
-str prettyAType(\iter-seps(AType symbol, list[AType] separators)) = "{<prettyAType(symbol)> <intercalate(" ", [ "\"<prettyAType(sep)>\"" | sep <- separators, !isLayoutAType(sep) ])>}+";
-str prettyAType(\iter-star-seps(AType symbol, list[AType] separators)) = "{<prettyAType(symbol)> <intercalate(" ", [ "\"<prettyAType(sep)>\"" | sep <- separators, !isLayoutAType(sep) ])>}*";
-str prettyAType(\alt(set[AType] alternatives)) = "( <intercalate(" | ", [ prettyAType(a) | a <- alternatives ])> )" when size(alternatives) > 1;
+str prettyAType(\iter-seps(AType symbol, list[AType] separators)) = size(seps) == 0 ? prettyAType(iter(symbol)) : "{<prettyAType(symbol)> <intercalate(" ", seps)>}+" when seps := [ "\"<prettyAType(sep)>\"" | sep <- separators, !isLayoutAType(sep) ];
+str prettyAType(\iter-star-seps(AType symbol, list[AType] separators)) = size(seps) == 0 ? prettyAType(\iter-star(symbol)) :  "{<prettyAType(symbol)> <intercalate(" ", seps)>}*" when seps := [ "\"<prettyAType(sep)>\"" | sep <- separators, !isLayoutAType(sep) ];
+str prettyAType(\alt(set[AType] alternatives)) = "( <intercalate(" | ", [ prettyAType(a) | a <- alternatives ])> )" when size(alternatives) > 0;
 str prettyAType(\seq(list[AType] sequence)) = "( <intercalate(" ", [ prettyAType(a) | a <- sequence ])> )" when size(sequence) > 1;
 str prettyAType(\conditional(AType symbol, set[ACondition] conditions)) = "<prettyAType(symbol)> { <intercalate(" ", [ prettyPrintCond(cond) | cond <- conditions ])> }";
 default str prettyAType(AType s) = "<s>"; //"<type(s,())>";
@@ -141,6 +148,12 @@ private str prettyPrintCond("a-begin-of-line"()) = "^";
 private str prettyPrintCond("a-end-of-line"()) = "$";
 private str prettyPrintCond("a-except"(str label)) = "!<label>";
 
+private str prettyAssoc(\aleft()) = "left";
+private str prettyAssoc(\aright()) = "right";
+private str prettyAssoc(\aassoc()) = "assoc";
+private str prettyAssoc(\a-non-assoc()) = "non-assoc";
+private default str prettyAssoc(v) = "<v>";
+
 @doc{Rascal abstract types to classic Symbols}
 Symbol atype2symbol(AType tp){
     //println("atype2symbol: <tp>");
diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/check/Checker.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/check/Checker.rsc
index 16c8ca3a063..a6363b66e7c 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/check/Checker.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/check/Checker.rsc
@@ -587,7 +587,7 @@ list[ModuleMessages] check(list[loc] moduleLocs, RascalCompilerConfig compilerCo
 list[ModuleMessages] reportModuleMessages(ModuleStatus ms){
     moduleIds = domain(ms.moduleLocs);
     messagesNoModule = {*ms.messages[mid] | MODID mid <- ms.messages, (mid notin moduleIds || mid notin ms.moduleLocs)} + toSet(ms.pathConfig.messages);
-    msgs = [ program(mid, (ms.messages[mid] ? {}) + messagesNoModule) | MODID mid <- moduleIds ];
+    msgs = [ program(ms.moduleLocs[mid], (ms.messages[mid] ? {}) + messagesNoModule) | MODID mid <- moduleIds ];
     if(isEmpty(msgs) && !isEmpty(messagesNoModule)){
         msgs = [ program(|unknown:///|, messagesNoModule) ];
     }
diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectDataDeclaration.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectDataDeclaration.rsc
index b33a79cd91c..2f0dcd52f02 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectDataDeclaration.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectDataDeclaration.rsc
@@ -72,7 +72,7 @@ void dataDeclaration(Tags tags, Declaration current, list[Variant] variants, Col
     dt.md5 = normalizedMD5Hash(adtName, dataCounter);
     dataCounter += 1;
     if(!isEmpty(commonKeywordParameterList)) dt.commonKeywordFields = commonKeywordParameterList;
-    c.define("<userType.name>", dataId(), current, dt);
+    c.define(userType.name, dataId(), current, dt);
        
     adtParentScope = c.getScope();
     c.enterScope(current);
@@ -142,7 +142,7 @@ void collect(current:(Variant) `<Name name> ( <{TypeArg ","}* arguments> <Keywor
                 fieldType = ta.\type;
                 dt = defType([fieldType], makeFieldType(fieldName, fieldType));
                 dt.md5 = normalizedMD5Hash(currentModuleName, adtName, name, current);
-                c.define("<ta.name>", fieldId(), ta.name, dt);
+                c.define(ta.name, fieldId(), ta.name, dt);
             }
         }
         
@@ -153,13 +153,13 @@ void collect(current:(Variant) `<Name name> ( <{TypeArg ","}* arguments> <Keywor
             kwfType = kwf.\type;
             dt = defType([kwfType], makeKeywordFieldType(fieldName, kwf));
             dt.md5 = normalizedMD5Hash(currentModuleName, adtName, dataCounter, name, consArity, kwfType, fieldName);
-            c.define("<kwf.name>", keywordFieldId(), kwf.name, dt);  
+            c.define(kwf.name, keywordFieldId(), kwf.name, dt);  
         }
     
         scope = c.getScope();
         c.enterScope(current);
             args = "<for(arg <- arguments){><arg is named ? "<arg.\type> <arg.name>" : "<arg>"> <}>";
-            c.defineInScope(adtParentScope, "<name>", constructorId(), name, defType(adt + formals + kwFormals + commonKwFormals,
+            c.defineInScope(adtParentScope, name, constructorId(), name, defType(adt + formals + kwFormals + commonKwFormals,
                 AType(Solver s){
                     adtType = s.getType(adt);
                     kwFormalTypes = [kwField(s.getType(kwf.\type)[alabel=prettyPrintName(kwf.name)], prettyPrintName(kwf.name), currentModuleName, kwf.expression) | kwf <- kwFormals /*+ commonKwFormals*/];
diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectDeclaration.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectDeclaration.rsc
index 9b13ab37dd2..1d689c4441c 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectDeclaration.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectDeclaration.rsc
@@ -92,7 +92,7 @@ void collect(Module current, Collector c){
     if(deprecated){
         c.report(warning(header.name, "Deprecated module %v%v", mname, isEmpty(deprecationMessage) ? "" : ": <deprecationMessage>"));
     }
-    c.define("<header.name>", moduleId(), current, defType(tmod));
+    c.define(header.name, moduleId(), current, defType(tmod));
 
     c.push(key_current_module, mname);
     c.enterScope(current);
@@ -192,7 +192,7 @@ void collect(current: (Declaration) `<Tags tags> <Visibility visibility> <Type v
             if(isWildCard(vname)){
                 c.report(warning(var, "Variable names starting with `_` are deprecated; only allowed to suppress warning on unused variables"));
             }
-            c.defineInScope(scope, "<var.name>", moduleVariableId(), var.name, dt);
+            c.defineInScope(scope, var.name, moduleVariableId(), var.name, dt);
 
             if(var is initialized){
                 initial = var.initial;
@@ -238,7 +238,7 @@ void collect(current: (Declaration) `<Tags tags> <Visibility visibility> anno <T
     // if(isWildCard(pname)){
     //     c.report(error(name, "Annotation names starting with `_` are deprecated; only allowed to suppress warning on unused variables"));
     // }
-    c.define("<name>", annoId(), current, dt);
+    c.define(name, annoId(), current, dt);
     collect(tags, annoType, onType, c);
 }
 
@@ -253,7 +253,7 @@ void collect(current: (KeywordFormal) `<Type kwType> <Name name> = <Expression e
          dt = defType([kwType], makeFieldType(kwformalName, kwType));
     }
     dt.md5 = normalizedMD5Hash(current);
-    c.define("<name>", keywordFormalId(), current, dt);
+    c.define(name, keywordFormalId(), current, dt);
     c.calculate("keyword formal", current, [kwType, expression],
         AType(Solver s){
             expType = s.getType(expression);
@@ -432,7 +432,7 @@ void collect(current: (FunctionDeclaration) `<FunctionDeclaration decl>`, Collec
         endUseBoundedTypeParameters(c);
 
         dt.md5 = normalizedMD5Hash(md5Contrib);
-        c.defineInScope(parentScope, "<fname>", functionId(), current, dt);
+        c.defineInScope(parentScope, fname, functionId(), current, dt);
     c.leaveScope(decl);
     c.pop(currentFunction);
     if(isEmpty(fstk)){
@@ -617,7 +617,7 @@ private tuple[set[str], rel[str,Type]] computeBoundsAndDefineTypeParams(Signatur
             c.fact(tp, tp.name);
         } else {
             seenInParams += tpname;
-            c.define("<tp.name>", typeVarId(), tp.name,
+            c.define(tp.name, typeVarId(), tp.name,
                 defType(toList(typeParamBounds[tpname]), makeBoundDef(tp, typeParamBounds, closed=false)));
             c.fact(tp, tp.name);
         }
@@ -761,7 +761,7 @@ void collect (current: (Declaration) `<Tags tags> <Visibility visibility> alias
     //     c.report(warning(name, "Alias names starting with `_` are deprecated; only allowed to suppress warning on unused variables"));
     // }
 
-    c.define("<name>", aliasId(), current, defType([base], AType(Solver s) { return s.getType(base); })[md5 = normalizedMD5Hash(md5Contrib4Tags(tags), visibility, name, base)]);
+    c.define(name, aliasId(), current, defType([base], AType(Solver s) { return s.getType(base); })[md5 = normalizedMD5Hash(md5Contrib4Tags(tags), visibility, name, base)]);
     c.enterScope(current);
         collect(tags, base, c);
     c.leaveScope(current);
@@ -785,7 +785,7 @@ void collect (current: (Declaration) `<Tags tags> <Visibility visibility> alias
         append tp.typeVar;
     }
 
-    c.define("<name>", aliasId(), name, defType(typeParams + base, AType(Solver s){
+    c.define(name, aliasId(), name, defType(typeParams + base, AType(Solver s){
         bindings = ();
         params = for(int i <- index(typeParams)){
             ptype = s.getType(typeParams[i]);
diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectLiteral.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectLiteral.rsc
index 04f608d10e8..b42c81d1d7e 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectLiteral.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectLiteral.rsc
@@ -98,7 +98,7 @@ void collect(current: (ConcreteHole) `\< <Sym symbol> <Name name> \>`, Collector
               c.useLub(name, {formalOrPatternFormal(c)});
            } else {
                c.push(patternNames, uname);
-               c.define("<name>", formalOrPatternFormal(c), name, defLub([symbol], AType(Solver s) { return s.getType(symbol); }));
+               c.define(name, formalOrPatternFormal(c), name, defLub([symbol], AType(Solver s) { return s.getType(symbol); }));
            }
         }
     }
diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectOperators.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectOperators.rsc
index 7c00a508086..6501a9ef264 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectOperators.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectOperators.rsc
@@ -620,7 +620,7 @@ void collect(current: (Expression) `<Pattern pat> \<- <Expression expression>`,
             } else  
                 throw TypeUnavailable();
           
-            c.define("<name>", formalOrPatternFormal(c), name, defType(patType));
+            c.define(name, formalOrPatternFormal(c), name, defType(patType));
             c.fact(pat, patType);
             c.fact(current, abool());
             return;  
diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectPattern.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectPattern.rsc
index c1073361e74..bdec5b2125c 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectPattern.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectPattern.rsc
@@ -50,7 +50,7 @@ void collect(RegExp regExp, Collector c){
     if( (RegExp)`\<<Name name>\>` := regExp){
         c.use(name, variableRoles);
     } else if ((RegExp)`\<<Name name>:<NamedRegExp* regexps>\>` := regExp){
-        c.define("<name>", formalOrPatternFormal(c), name, defType(astr()));
+        c.define(name, formalOrPatternFormal(c), name, defType(astr()));
         collect(name, regexps, c);
     }
     c.fact(regExp, astr());
@@ -109,7 +109,7 @@ void collect(current: (Pattern) `<Type tp> <Name name>`, Collector c){
                 }
             }
        }
-       c.define("<name>", formalOrPatternFormal(c), name, defType(tp));
+       c.define(name, formalOrPatternFormal(c), name, defType(tp));
     } else {
         c.fact(name, tp);
         //c.calculate("variable <name>", name, [tp], AType(Solver s) { return s.getType(tp); });
@@ -129,7 +129,7 @@ void collectAsVarArg(current: (Pattern) `<Type tp> <Name name>`, Collector c){
             });
        } else {
           c.push(patternNames, <uname, getLoc(name)>);
-          c.define("<name>", formalOrPatternFormal(c), name, defType([tp], AType(Solver s){ 
+          c.define(name, formalOrPatternFormal(c), name, defType([tp], AType(Solver s){ 
             res = alist(s.getType(tp))[alabel=uname];
             return res;
              }));
@@ -158,7 +158,7 @@ void collect(current: (Pattern) `<QualifiedName name>`,  Collector c){
        if(!isEmpty(qualifier)) c.report(error(name, "Qualifier not allowed"));
        if(isTopLevelParameter(c)){
           c.fact(current, avalue(alabel=unescape(prettyPrintBaseName(name))));  
-          c.define("<name.names[-1]>", formalId(), name, defLub([], AType(Solver _) { return avalue(alabel=unescape(prettyPrintBaseName(name))); }));
+          c.define(name.names[-1], formalId(), name, defLub([], AType(Solver _) { return avalue(alabel=unescape(prettyPrintBaseName(name))); }));
        } else {
           if(c.isAlreadyDefined(base, name)){
             c.use(name, {variableId(), moduleVariableId(), formalId(), nestedFormalId(), patternVariableId(), constructorId()});
@@ -166,7 +166,7 @@ void collect(current: (Pattern) `<QualifiedName name>`,  Collector c){
           } else {
             tau = c.newTypeVar(name);
             c.fact(name, tau); //<====
-            c.define("<name.names[-1]>", formalOrPatternFormal(c), name, defLub([], AType(Solver s) { 
+            c.define(name.names[-1], formalOrPatternFormal(c), name, defLub([], AType(Solver s) { 
                 return s.getType(tau)[alabel=unescape(prettyPrintBaseName(name))]; 
             }));
           }
@@ -223,7 +223,7 @@ void collectSplicePattern(Pattern current, Pattern argument,  Collector c){
             }
           }   
           
-          c.define("<argName>", formalOrPatternFormal(c), argName, defType([tp], 
+          c.define(argName, formalOrPatternFormal(c), argName, defType([tp], 
                AType(Solver s){ return inSet ? aset(s.getType(tp)) : alist(s.getType(tp)); }));     
        } else {
           c.calculate("typed anonymous variable in splice pattern", argName, [tp], 
@@ -246,7 +246,7 @@ void collectSplicePattern(Pattern current, Pattern argument,  Collector c){
            if(isTopLevelParameter(c)){
               c.fact(current, avalue());
               if(!isEmpty(qualifier)) c.report(error(argName, "Qualifier not allowed"));
-              c.define("<argName.names[-1]>", formalId(), argName, defLub([], AType(Solver _) { return avalue(); }));
+              c.define(argName.names[-1], formalId(), argName, defLub([], AType(Solver _) { return avalue(); }));
            } else {
               if(c.isAlreadyDefined("<argName>", argName)) {
                   c.use(argName, {variableId(), moduleVariableId(), formalId(), nestedFormalId(), patternVariableId()});
@@ -255,7 +255,7 @@ void collectSplicePattern(Pattern current, Pattern argument,  Collector c){
                   tau = c.newTypeVar(current); // <== argName;
                   c.fact(current, tau);    // <===
                   if(!isEmpty(qualifier)) c.report(error(argName, "Qualifier not allowed"));
-                  c.define("<argName.names[-1]>", formalOrPatternFormal(c), argName, 
+                  c.define(argName.names[-1], formalOrPatternFormal(c), argName, 
                             defLub([], AType(Solver s) { 
                             return inSet ? makeSetType(s.getType(tau)) : makeListType(s.getType(tau));}));
               }
@@ -320,7 +320,7 @@ void collect(current: (Pattern) `<Name name> : <Pattern pattern>`, Collector c){
     } else {
         c.push(patternNames, <uname, getLoc(name)>);
         scope = c.getScope();
-        c.define("<name>", formalOrPatternFormal(c), name, 
+        c.define(name, formalOrPatternFormal(c), name, 
                  defLub([pattern], AType(Solver s) { 
                     try{
                         return s.getType(pattern);
@@ -349,7 +349,7 @@ void collect(current: (Pattern) `<Type tp> <Name name> : <Pattern pattern>`, Col
                 }
             }
         }   
-        c.define("<name>", formalOrPatternFormal(c), name, defType([tp], AType(Solver s){ return s.getType(tp); }));
+        c.define(name, formalOrPatternFormal(c), name, defType([tp], AType(Solver s){ return s.getType(tp); }));
     }
 }
 
diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectStatement.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectStatement.rsc
index 400912276ac..94daa312cbb 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectStatement.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectStatement.rsc
@@ -87,7 +87,7 @@ void collect(current: (Statement) `<Label label> <Visit vst>`, Collector c){
         scope = c.getScope();
         c.setScopeInfo(scope, visitOrSwitchScope(), visitOrSwitchInfo(vst.subject, true));
         if(label is \default){
-            c.define("<label.name>", labelId(), label.name, defType(avoid()));
+            c.define(label.name, labelId(), label.name, defType(avoid()));
         }
         c.require("non-void", vst.subject, [], makeNonVoidRequirement(vst.subject, "Subject of visit"));
         c.fact(current, vst.subject);
@@ -115,7 +115,7 @@ void collect(current: (Expression) `<Label label> <Visit vst>`, Collector c){
         scope = c.getScope();
         c.setScopeInfo(scope, visitOrSwitchScope(), visitOrSwitchInfo(vst.subject, true));
         if(label is \default){
-            c.define("<label.name>", labelId(), label.name, defType(avoid()));
+            c.define(label.name, labelId(), label.name, defType(avoid()));
         }
         c.calculate("visit", current, [vst.subject],
             AType(Solver s){
@@ -293,7 +293,7 @@ void collect(current: (Statement) `<Label label> while( <{Expression ","}+ condi
         loopName = "";
         if(label is \default){
             loopName = prettyPrintName(label.name);
-            c.define("<label.name>", labelId(), label.name, defType(avoid()));
+            c.define(label.name, labelId(), label.name, defType(avoid()));
         }
         c.setScopeInfo(c.getScope(), loopScope(), loopInfo(loopName, [])); // record appends in body, initially []
         condList = [cond | Expression cond <- conditions];
@@ -339,7 +339,7 @@ void collect(current: (Statement) `<Label label> do <Statement body> while ( <Ex
         loopName = "";
         if(label is \default){
             loopName = prettyPrintName(label.name);
-            c.define("<label.name>", labelId(), label.name, defType(avoid()));
+            c.define(label.name, labelId(), label.name, defType(avoid()));
         }
         c.setScopeInfo(c.getScope(), loopScope(), loopInfo(loopName, [])); // appends in body
         c.require("do statement", current, [body, condition], void (Solver s){ checkConditions([condition], s); });
@@ -361,7 +361,7 @@ void collect(current: (Statement) `<Label label> for( <{Expression ","}+ conditi
         loopName = "";
         if(label is \default){
             loopName = prettyPrintName(label.name);
-            c.define("<label.name>", labelId(), label.name, defType(avoid()));
+            c.define(label.name, labelId(), label.name, defType(avoid()));
         }
         c.setScopeInfo(c.getScope(), loopScope(), loopInfo(loopName, [])); // appends in body
         condList = [cond | Expression cond <- conditions];
@@ -453,7 +453,7 @@ void collect(current:(Statement) `continue <Target target>;`, Collector c){
 void collect(current: (Statement) `<Label label> if( <{Expression ","}+ conditions> ) <Statement thenPart>`,  Collector c){
     c.enterCompositeScope([conditions, thenPart]); // thenPart may refer to variables defined in conditions
         if(label is \default){
-            c.define("<label.name>", labelId(), label.name, defType(avoid()));
+            c.define(label.name, labelId(), label.name, defType(avoid()));
         }
         condList = [cond | Expression cond <- conditions];
         c.fact(current, avalue());
@@ -472,7 +472,7 @@ void collect(current: (Statement) `<Label label> if( <{Expression ","}+ conditio
 void collect(current: (Statement) `<Label label> if( <{Expression ","}+ conditions> ) <Statement thenPart> else <Statement elsePart>`,  Collector c){
     c.enterCompositeScope([conditions, thenPart]);   // thenPart may refer to variables defined in conditions; elsePart may not
         if(label is \default){
-            c.define("<label.name>", labelId(), label.name, defType(avoid()));
+            c.define(label.name, labelId(), label.name, defType(avoid()));
         }
         condList = [cond | cond <- conditions];
 
@@ -495,7 +495,7 @@ void collect(current: (Statement) `<Label label> if( <{Expression ","}+ conditio
 void collect(current: (Statement) `<Label label> switch ( <Expression e> ) { <Case+ cases> }`, Collector c){
     c.enterScope(current);
         if(label is \default){
-            c.define("<label.name>", labelId(), label.name, defType(avoid()));
+            c.define(label.name, labelId(), label.name, defType(avoid()));
         }
         scope = c.getScope();
         c.setScopeInfo(scope, visitOrSwitchScope(), visitOrSwitchInfo(e, false));
@@ -605,7 +605,7 @@ void collect(current: (Catch) `catch <Pattern pattern>: <Statement body>`, Colle
 void collect(current: (Statement) `<Label label> { <Statement+ statements> }`, Collector c){
     c.enterScope(current);
         if(label is \default){
-           c.define("<label.name>", labelId(), label.name, defType(avoid()));
+           c.define(label.name, labelId(), label.name, defType(avoid()));
         }
         stats = [ s | Statement s <- statements ];
         c.calculate("non-empty block statement", current, [stats[-1]],  AType(Solver s) { return s.getType(stats[-1]); } );
@@ -723,7 +723,7 @@ private void checkAssignment(Statement current, (Assignable) `<QualifiedName nam
             if(c.isAlreadyDefined("<name>", name)){
                 c.use(name, variableRoles);
             } else {
-                c.define("<name.names[-1]>", variableId(), name, defLub([statement],
+                c.define(name.names[-1], variableId(), name, defLub([statement],
                     AType(Solver s){
                         // TODO: this seemingly redundant call is needed; suspicion: the interpreter does not
                         // handle the combination of return and possible exception thrown by s.getType properly
@@ -736,7 +736,7 @@ private void checkAssignment(Statement current, (Assignable) `<QualifiedName nam
              if(c.isAlreadyDefined("<name>", name)){
                 c.use(name, variableRoles);
             } else {
-                c.define("<name.names[-1]>", variableId(), name, defLub([statement, name],  AType(Solver s){
+                c.define(name.names[-1], variableId(), name, defLub([statement, name],  AType(Solver s){
                     return computeAssignmentRhsType(statement, s.getType(name), operator, s.getType(statement), s);
                 }));
             }
@@ -1104,7 +1104,7 @@ private void checkAssignment(Statement current, receiver: (Assignable) `\< <{Ass
    elms = [elm | elm <- elements];
    namesInRhs = getNames(rhs);
    taus = [c.newTypeVar(nm) | nm <- names];
-   for(int i <- index(names), flatNames[i] notin namesInRhs){c.define("<names[i]>", variableId(), names[i], defLub([rhs], makeDef(i)));}
+   for(int i <- index(names), flatNames[i] notin namesInRhs){c.define(names[i], variableId(), names[i], defLub([rhs], makeDef(i)));}
 
    for(name <- names) c.useLub(name, variableRoles);
 
@@ -1217,7 +1217,7 @@ void collect(current: (Statement) `<Type varType> <{Variable ","}+ variables>;`,
     scope = c.getScope();
     c.enterScope(current); // wrap in extra scope to isolate variables declared in complex (function) types
         for(var <- variables){
-            c.defineInScope(scope, "<var.name>", variableId(), var.name, defType([varType], makeGetSyntaxType(varType)));
+            c.defineInScope(scope, var.name, variableId(), var.name, defType([varType], makeGetSyntaxType(varType)));
 
             if(var is initialized){
                 initial = var.initial;
diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectSyntaxDeclaration.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectSyntaxDeclaration.rsc
index afcf4beaf00..c5e9f7f18f0 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectSyntaxDeclaration.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectSyntaxDeclaration.rsc
@@ -82,7 +82,7 @@ void declareSyntax(SyntaxDefinition current, SyntaxRole syntaxRole, IdRole idRol
         syndefCounter += 1;
 
         // Define the syntax symbol itself and all labelled alternatives as constructors
-        c.define(nonterminalType.adtName, idRole, current, dt);
+        c.define(defsym2IdTree(defined), idRole, current, dt);
 
         adtParentScope = c.getScope();
         c.enterScope(current);
@@ -181,7 +181,7 @@ void collect(current: (Prod) `<ProdModifier* modifiers> <Name name> : <Sym* syms
         qualName = "<SyntaxDefinition sd := adt ? sd.defined.nonterminal : "???">_<uname>";
 
          // Define the constructor
-        c.defineInScope(adtParentScope, "<name>", constructorId(), name, defType([current],
+        c.defineInScope(adtParentScope, name, constructorId(), name, defType([current],
             AType(Solver s){
                 ptype = s.getType(current);
                 if(aprod(AProduction cprod) := ptype){
diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectType.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectType.rsc
index 42222797bb7..8c617e9c020 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectType.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/check/CollectType.rsc
@@ -528,7 +528,7 @@ void collect(current:(Sym) `& <Nonterminal n>`, Collector c){
             c.use(n, {typeVarId() });
             //println("Use <pname> at <current@\loc>");
         } else {
-            c.define("<n>", typeVarId(), n, defType(aparameter(pname,treeType, closed=closed)));
+            c.define(n, typeVarId(), n, defType(aparameter(pname,treeType, closed=closed)));
             //println("Define <pname> at <current@\loc>");
         }
         c.fact(current, n);
@@ -585,7 +585,7 @@ void collect(current:(Sym) `<Sym symbol> <NonterminalLabel n>`, Collector c){
     //   * either it is a Nonterminal name and the rule for Nonterminal covers this requirement
     //   * or it is a more complex Sym which are non-terminals by definition
 
-    c.define("<n>", fieldId(), n, defType([symbol],
+    c.define(n, fieldId(), n, defType([symbol],
         AType(Solver s){
             res = s.getType(symbol)[alabel=un];
           return res;
@@ -825,7 +825,7 @@ void collect(current:(TypeVar) `& <Name n>`, Collector c){
             } else {
                 throw "collect TypeVar: currentAdt not found";
             }
-            c.define("<n>", typeVarId(), n, defType(aparameter(pname, bound, closed=closed)));
+            c.define(n, typeVarId(), n, defType(aparameter(pname, bound, closed=closed)));
         }
         c.calculate("type parameter without bound", current, [n], AType (Solver s) { return s.getType(n)[closed=closed]; });
         return;
@@ -863,7 +863,7 @@ void collect(current: (TypeVar) `& <Name n> \<: <Type tp>`, Collector c){
             c.use(n, {typeVarId() });
             //if(debugTP)println("Use <pname> at <current@\loc>");
         } else {
-            c.define("<n>", typeVarId(), n, defTypeCall([getLoc(tp)], AType(Solver s) {return aparameter(pname,s.getType(tp), closed=closed); }));
+            c.define(n, typeVarId(), n, defTypeCall([getLoc(tp)], AType(Solver s) {return aparameter(pname,s.getType(tp), closed=closed); }));
             //if(debugTP)println("Define <pname> at <current@\loc>");
         }
         c.calculate("type parameter, 1", current, [n, tp], AType (Solver s) { return s.getType(n)[closed=closed]; });
diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/check/Import.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/check/Import.rsc
index d00c3d87907..6b39268e7ef 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/check/Import.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/check/Import.rsc
@@ -389,7 +389,7 @@ tuple[map[MODID,TModel], ModuleStatus] prepareForCompilation(set[MODID] componen
             if(hasProperty(imp, ms, parse_error()) || hasNotProperty(imp, ms, checked())){
                 dependencies_ok = false;
                 cause = hasProperty(imp, ms, rsc_not_found()) ? "module not found" : "due to syntax error";
-                ms.messages[m] = (ms.messages[imp] ? {}) + error("<imp in m_imports[imp] ? "Imported" : "Extended"> module <imp> could not be checked (<cause>)", m);
+                ms.messages[m] = (ms.messages[imp] ? {}) + error("<imp in m_imports ? "Imported" : "Extended"> module <imp> could not be checked (<cause>)", m);
             }
         }
         if(!dependencies_ok){
@@ -508,6 +508,8 @@ ModuleStatus doSaveModule(set[MODID] component, map[MODID,set[MODID]] m_imports,
         m1.defines = toSet(defs);
 
         m1.definitions = ( def.defined : def | Define def <- m1.defines);  // TODO this is derived info, can we derive it later?
+        m1.define2id = tm.define2id;
+        
         // Remove default expressions and fragments
         m1 = visit(m1) {
                     case kwField(AType atype, str fieldName, str definingModule, Expression _defaultExp) => kwField(atype, fieldName, definingModule)
diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/check/tests/StaticTestingUtils.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/check/tests/StaticTestingUtils.rsc
index fe0d2d576f3..e6f587d002b 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/check/tests/StaticTestingUtils.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/check/tests/StaticTestingUtils.rsc
@@ -248,9 +248,7 @@ bool validateUseDefs(str moduleName, map[str, tuple[int, set[int]]] defuses, Mod
 				throw "Missing use <u> for <v>";
 			}
 			potentialDefs = foundUseDefs[occ[u]];
-			// We us containement here, give how the type chcker works at the moment.
-			// An equality test would be better.
-			if(isEmpty(potentialDefs) || !any(d <- potentialDefs, isContainedIn(occ[def], d, tm.logical2physical))){
+			if(isEmpty(potentialDefs) || !any(d <- potentialDefs, occ[def] == (tm.logical2physical[d] ? d))){
 				throw "Missing def for use <u> of <v>";
 			}
 		 }
diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/check/tests/UseDefTests.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/check/tests/UseDefTests.rsc
index eb11cc05d52..8a812d28544 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/check/tests/UseDefTests.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/check/tests/UseDefTests.rsc
@@ -77,6 +77,12 @@ test bool kwfield1() =
                 }",
                 ("n": <0, {1, 2}>)); 
 
+test bool \syntax() =
+    useDefOK("module Syntax
+                syntax C = \"c\";
+                syntax D = C;",
+                ("C": <0, {1}>));
+
 test bool syntaxField1() =
     useDefOK("module SyntaxField
                 syntax C = \"c\";
diff --git a/src/org/rascalmpl/compiler/lang/rascalcore/compile/Examples/A.rsc b/src/org/rascalmpl/compiler/lang/rascalcore/compile/Examples/A.rsc
index c81a74c86ba..5b04a1738db 100644
--- a/src/org/rascalmpl/compiler/lang/rascalcore/compile/Examples/A.rsc
+++ b/src/org/rascalmpl/compiler/lang/rascalcore/compile/Examples/A.rsc
@@ -49,4 +49,8 @@ int f(int n) = n;
 // @javaClass{org.rascalmpl.library.Prelude}
 // java list[&T] sort(list[&T] l, bool (&T a, &T b) less) ;
                          
- 
\ No newline at end of file
+ 
+ 
+data X1 = z();
+// anno int X1@xz;
+// int doY(X1 x) = x@xz;        
diff --git a/src/org/rascalmpl/library/util/Reflective.java b/src/org/rascalmpl/library/util/Reflective.java
index 0145545734f..c6567e6de57 100644
--- a/src/org/rascalmpl/library/util/Reflective.java
+++ b/src/org/rascalmpl/library/util/Reflective.java
@@ -31,6 +31,7 @@
 import org.rascalmpl.library.lang.rascal.syntax.RascalParser;
 import org.rascalmpl.library.util.PathConfig.RascalConfigMode;
 import org.rascalmpl.parser.Parser;
+import org.rascalmpl.parser.gtd.exception.ParseError;
 import org.rascalmpl.parser.gtd.io.InputConverter;
 import org.rascalmpl.parser.gtd.result.out.DefaultNodeFlattener;
 import org.rascalmpl.parser.gtd.result.out.INodeFlattener;
@@ -244,6 +245,8 @@ public static ITree parseModuleWithSpaces(ISourceLocation loc) {
 			return new RascalParser().parse(Parser.START_MODULE, loc.getURI(), getResourceContent(loc), INodeFlattener.UNLIMITED_AMB_DEPTH, new NoActionExecutor(), new DefaultNodeFlattener<IConstructor, ITree, ISourceLocation>(), new UPTRNodeFactory(true));
 		} catch (IOException e) {
 			throw RuntimeExceptionFactory.io(e);
+		} catch (ParseError e) {
+			throw RuntimeExceptionFactory.parseError(e.getLocation());
 		}
 	}
 
diff --git a/src/org/rascalmpl/uri/URIResolverRegistry.java b/src/org/rascalmpl/uri/URIResolverRegistry.java
index 929844134fe..79b5468115d 100644
--- a/src/org/rascalmpl/uri/URIResolverRegistry.java
+++ b/src/org/rascalmpl/uri/URIResolverRegistry.java
@@ -78,7 +78,6 @@ private URIResolverRegistry() {
 		loadServices();
 	}
 
-
 	/**
 	 * Use with care! This (expensive) reinitialization method clears all caches of all resolvers by
 	 * reloading them from scratch.
@@ -506,7 +505,11 @@ private ISourceLocationOutput getOutputResolver(String scheme) {
 					return result;
 				}
 			}
-			if (externalRegistry != null && externalRegistry.supportsOutput(scheme)) {
+			// only return an external registry if the input is also going to an external resolver
+			// as input resolvers are quite common, but output less, and we don't want all of them
+			// to always go via the external registries (just to receive an exception)
+			var inputResolver = getInputResolver(scheme);
+			if (externalRegistry != null && externalRegistry.supportsOutput(scheme) && inputResolver == externalRegistry) {
 				return externalRegistry;
 			}
 		}
diff --git a/src/org/rascalmpl/uri/URIUtil.java b/src/org/rascalmpl/uri/URIUtil.java
index 829001331a5..45b76d98e56 100644
--- a/src/org/rascalmpl/uri/URIUtil.java
+++ b/src/org/rascalmpl/uri/URIUtil.java
@@ -508,8 +508,4 @@ else if (index != -1) {
 
 		return URIUtil.changePath(location, path);
     }
-	
-    public static URI invalidURI() {
-        return rootScheme("invalid");
-    }
 }
diff --git a/src/org/rascalmpl/uri/resolvers.config b/src/org/rascalmpl/uri/resolvers.config
index 2b599b78ccc..c25d506cf23 100644
--- a/src/org/rascalmpl/uri/resolvers.config
+++ b/src/org/rascalmpl/uri/resolvers.config
@@ -14,4 +14,6 @@ org.rascalmpl.uri.file.CurrentWorkingDriveResolver
 org.rascalmpl.uri.file.UNCResolver
 org.rascalmpl.uri.file.SystemPathURIResolver
 org.rascalmpl.uri.libraries.MemoryResolver
+org.rascalmpl.uri.unsupported.UnknownURIResolver
+org.rascalmpl.uri.unsupported.LibraryURIResolver
 
diff --git a/src/org/rascalmpl/uri/unsupported/LibraryURIResolver.java b/src/org/rascalmpl/uri/unsupported/LibraryURIResolver.java
new file mode 100644
index 00000000000..458180b73b8
--- /dev/null
+++ b/src/org/rascalmpl/uri/unsupported/LibraryURIResolver.java
@@ -0,0 +1,7 @@
+package org.rascalmpl.uri.unsupported;
+
+public class LibraryURIResolver extends UnsupportedURIResolver {
+    public LibraryURIResolver() {
+        super("lib", "The lib scheme has been removed, please rewrite to mvn scheme or use getResource");
+    }
+}
diff --git a/src/org/rascalmpl/uri/unsupported/UnknownURIResolver.java b/src/org/rascalmpl/uri/unsupported/UnknownURIResolver.java
new file mode 100644
index 00000000000..78013e2489e
--- /dev/null
+++ b/src/org/rascalmpl/uri/unsupported/UnknownURIResolver.java
@@ -0,0 +1,9 @@
+package org.rascalmpl.uri.unsupported;
+
+import org.rascalmpl.uri.URIUtil;
+
+public class UnknownURIResolver extends UnsupportedURIResolver {
+    public UnknownURIResolver() {
+        super(URIUtil.unknownLocation().getScheme(), "The unknown scheme cannot be read/written to, it indicates someone didn't know the location");
+    }
+}
diff --git a/src/org/rascalmpl/uri/unsupported/UnsupportedURIResolver.java b/src/org/rascalmpl/uri/unsupported/UnsupportedURIResolver.java
new file mode 100644
index 00000000000..1914cee3b04
--- /dev/null
+++ b/src/org/rascalmpl/uri/unsupported/UnsupportedURIResolver.java
@@ -0,0 +1,125 @@
+package org.rascalmpl.uri.unsupported;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.util.function.Consumer;
+
+import org.rascalmpl.uri.FileAttributes;
+import org.rascalmpl.uri.ISourceLocationInputOutput;
+import org.rascalmpl.uri.ISourceLocationWatcher;
+
+import io.usethesource.vallang.ISourceLocation;
+
+abstract class UnsupportedURIResolver implements ISourceLocationInputOutput, ISourceLocationWatcher {
+
+    private final String scheme;
+    private final String message;
+
+    protected UnsupportedURIResolver(String scheme, String message) {
+        this.scheme = scheme;
+        this.message = message;
+    }
+
+    private IOException buildException() {
+        return new IOException(message);
+    }
+
+    @Override
+    public InputStream getInputStream(ISourceLocation uri) throws IOException {
+        throw buildException();
+    }
+
+    @Override
+    public boolean exists(ISourceLocation uri) {
+        return false;
+    }
+
+    @Override
+    public long lastModified(ISourceLocation uri) throws IOException {
+        throw buildException();
+    }
+
+    @Override
+    public long size(ISourceLocation uri) throws IOException {
+        throw buildException();
+    }
+
+    @Override
+    public boolean isDirectory(ISourceLocation uri) {
+        return false;
+    }
+
+    @Override
+    public boolean isFile(ISourceLocation uri) {
+        return false;
+    }
+
+    @Override
+    public boolean isReadable(ISourceLocation uri) throws IOException {
+        throw buildException();
+    }
+
+    @Override
+    public String[] list(ISourceLocation uri) throws IOException {
+        throw buildException();
+    }
+
+    @Override
+    public String scheme() {
+        return this.scheme;
+    }
+
+    @Override
+    public boolean supportsHost() {
+        return false;
+    }
+
+    @Override
+    public FileAttributes stat(ISourceLocation uri) throws IOException {
+        throw buildException();
+    }
+
+    @Override
+    public OutputStream getOutputStream(ISourceLocation uri, boolean append) throws IOException {
+        throw buildException();
+    }
+
+    @Override
+    public void mkDirectory(ISourceLocation uri) throws IOException {
+        throw buildException();
+    }
+
+    @Override
+    public void remove(ISourceLocation uri) throws IOException {
+        throw buildException();
+    }
+
+    @Override
+    public void setLastModified(ISourceLocation uri, long timestamp) throws IOException {
+        throw buildException();
+    }
+
+    @Override
+    public boolean isWritable(ISourceLocation uri) throws IOException {
+        throw buildException();
+    }
+
+    @Override
+    public void watch(ISourceLocation root, Consumer<ISourceLocationChanged> watcher, boolean recursive)
+        throws IOException {
+        throw buildException();
+    }
+
+    @Override
+    public void unwatch(ISourceLocation root, Consumer<ISourceLocationChanged> watcher, boolean recursive)
+        throws IOException {
+        throw buildException();
+    }
+
+    @Override
+    public boolean supportsRecursiveWatch() {
+        return false;
+    }
+    
+}
diff --git a/test/org/rascalmpl/test/repl/JlineParserTest.java b/test/org/rascalmpl/test/repl/JlineParserTest.java
index 1b3e9ee9a02..97e1d2ad7a2 100644
--- a/test/org/rascalmpl/test/repl/JlineParserTest.java
+++ b/test/org/rascalmpl/test/repl/JlineParserTest.java
@@ -16,7 +16,7 @@ private ParsedLine completeParser(String input) {
     }
 
     private ParsedLine completeParser(String input, int cursor) {
-        var parser = new RascalLineParser(l -> { throw new ParseError("rascal parser not supported in the test yet", URIUtil.invalidURI(), 0, 0, 0, 0, 0, 0); });
+        var parser = new RascalLineParser(l -> { throw new ParseError("rascal parser not supported in the test yet", URIUtil.unknownLocation().getURI(), 0, 0, 0, 0, 0, 0); });
 
         return parser.parse(input, cursor, ParseContext.COMPLETE);
     }

From 654eeb3dc5a4cbc2d82324e45e25d2dfa806e3f2 Mon Sep 17 00:00:00 2001
From: Toine Hartman <toine.hartman@swat.engineering>
Date: Wed, 19 Aug 2026 11:56:21 +0200
Subject: [PATCH 2/2] Ignore merge revert and re-application.

---
 .git-blame-ignore-revs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/.git-blame-ignore-revs b/.git-blame-ignore-revs
index 64c543262bf..d556b15bdc7 100644
--- a/.git-blame-ignore-revs
+++ b/.git-blame-ignore-revs
@@ -10,3 +10,7 @@ f5d0490e283e36e527821736b11f9b09163b67b6
 1b9801104c0e839e229c25f6a16b72a48e874594
 97fc3b0739f848c8277f2b2c2aae3530afff37a6
 a004c2604cef592975f60a572c4a03491b2f7971
+
+# Revert and re-application of a merge commit
+3d5369b35a00bddc085d722010baf329580b1c68
+b277ae88b653f039b576717f8d9ecd56e5dbd2fe