fix: reader #" #uuid dispatch, emitter metadata/fn/def fixes, runtime stubs

Reader: #" regex literals and #uuid"..." dispatch macros
Emitter: named fn support, fn metadata stripping, def len!=3 graceful
handling, loop binding metadata stripping, list-head-is-list call support
Runtime: cljRepeatedly, cljMakeHierarchy, cljDerive/Underive,
cljPrintlnStr, cljPrnStr, cljBinding, cljAset, cljVectorFn stubs

Results: 164/233 passed (70%), clojure.string 8/8 (100%)

src/emitter.nim

@@ -263,6 +263,15 @@ proc runtimeName(op: string): string =
   of "fnil": "cljFnil"
   of "intern": "cljIntern"
   of "to-array": "cljToArray"
+  of "repeatedly": "cljRepeatedly"
+  of "make-hierarchy": "cljMakeHierarchy"
+  of "derive": "cljDerive"
+  of "underive": "cljUnderive"
+  of "println-str": "cljPrintlnStr"
+  of "prn-str": "cljPrnStr"
+  of "binding": "cljBinding"
+  of "aset": "cljAset"
+  of "vector": "cljVectorFn"
   # ---- Type conversion ----
   of "float": "cljToFloat"
   of "int": "cljToInt"
@@ -279,7 +288,12 @@ proc emitSpecialForm(items: seq[CljVal], indent: int): string =
   let sp = indentStr(indent)
   let head = items[0]
   if head.kind != ckSymbol:
-    raise newException(EmitterError, "List head must be a symbol, got " & $head.kind)
+    # Head is not a symbol - evaluate as function call: ((fn ...) args...)
+    var argParts: seq[string] = @[]
+    for i in 1..<items.len:
+      argParts.add(emitExpr(items[i], indent))
+    let fnCode = emitExpr(head, 0)
+    return sp & "cljApply(" & fnCode & ", cljList(@[" & argParts.join(", ") & "]))"
   let op = resolveNsAlias(head.symName)
 
   # ---- Special forms (language constructs) ----
@@ -436,8 +450,17 @@ proc emitSpecialForm(items: seq[CljVal], indent: int): string =
     return sp & "discard cljNil()"
 
   of "def":
-    if items.len != 3:
-      raise newException(EmitterError, "def requires exactly 2 arguments")
+    if items.len < 3:
+      return sp & "cljNil()"
+    if items.len > 3:
+      # (def name docstring value) or similar - use last arg as value
+      let nameItem = items[1]
+      var valItem = items[^1]
+      if nameItem.kind == ckSymbol:
+        let mangled = mangleName(nameItem.symName)
+        let valCode = emitExpr(valItem, 0)
+        return sp & "let " & mangled & " = " & valCode
+      return sp & "cljNil()"
     var name = items[1]
     # Strip metadata: (with-meta sym meta) -> sym
     if name.kind == ckList and name.items.len == 3 and
@@ -518,7 +541,17 @@ proc emitSpecialForm(items: seq[CljVal], indent: int): string =
   of "fn":
     if items.len < 3:
       raise newException(EmitterError, "fn requires params and body")
-    let params = items[1]
+    var paramsIdx = 1
+    # Handle named fn: (fn name [params] body)
+    if items[1].kind == ckSymbol:
+      paramsIdx = 2
+    if paramsIdx >= items.len:
+      raise newException(EmitterError, "fn requires params and body")
+    var params = items[paramsIdx]
+    # Strip metadata from params
+    if params.kind == ckList and params.items.len == 3 and
+       params.items[0].kind == ckSymbol and params.items[0].symName == "with-meta":
+      params = params.items[1]
     if params.kind != ckVector:
       raise newException(EmitterError, "fn params must be a vector")
     var paramNames: seq[string] = @[]
@@ -675,8 +708,12 @@ proc emitSpecialForm(items: seq[CljVal], indent: int): string =
     var loopParams: seq[(string, string)] = @[]
     var li = 0
     while li < bindings.items.len:
-      let lname = bindings.items[li]
+      var lname = bindings.items[li]
       let lval = bindings.items[li+1]
+      # Strip metadata: (with-meta sym meta) -> sym
+      if lname.kind == ckList and lname.items.len == 3 and
+         lname.items[0].kind == ckSymbol and lname.items[0].symName == "with-meta":
+        lname = lname.items[1]
       if lname.kind != ckSymbol:
         raise newException(EmitterError, "loop binding name must be a symbol")
       loopParams.add((mangleName(lname.symName), emitExpr(lval, 0)))

src/reader.nim

@@ -291,6 +291,35 @@ proc readDispatch(s: string, i: var int): CljVal =
     inc i
     discard readForm(s, i)
     return nil
+  of '"':
+    # #"regex" — treat as string for now
+    inc i
+    var regexStr = ""
+    while i < s.len and s[i] != '"':
+      if s[i] == '\\' and i + 1 < s.len:
+        regexStr.add(s[i])
+        regexStr.add(s[i+1])
+        inc i
+      else:
+        regexStr.add(s[i])
+      inc i
+    if i < s.len: inc i  # skip closing "
+    return cljString(regexStr)
+  of 'u':
+    # #uuid"..." — read as string
+    inc i
+    if i + 4 < s.len and s[i..i+3] == "uuid":
+      i += 4
+      while i < s.len and s[i] == ' ': inc i
+      if i < s.len and s[i] == '"':
+        inc i
+        var uuidStr = ""
+        while i < s.len and s[i] != '"':
+          uuidStr.add(s[i])
+          inc i
+        if i < s.len: inc i
+        return cljString(uuidStr)
+    raise newException(ReaderError, "Unknown dispatch: #u")
   of '?':
     # Reader conditional: #?(:clj expr :cljs expr :default expr)
     # Read the next char - if '@' it's splicing version #?@