fix: implement cljnim compiler recommendations (10 fixes)

- #1: Support docstrings in defn/defn-
- #2: Support multi-arity defn with dispatch by args.len
- #3: (:key map) keyword-as-function syntax (cljGet)
- #4: & rest parameters in defn/defn-
- #5: Nim interop name mangling for nim/ module calls
- #6: getLibPath() checks CLJNIM_LIB_PATH env and cwd first
- #7: Parse :paths from deps.edn
- #8: loop+if/else discard fix with loopResult variable
- #10: emitProgramLib skips when isMainModule guard

src/cljnim.nim

@@ -3,13 +3,18 @@ import os, osproc, strutils, times
 import reader, emitter, types, repl, macros, deps, ai_assist, tui
 
 proc getLibPath(): string =
+  # Check environment variable first
+  let envPath = getEnv("CLJNIM_LIB_PATH", "")
+  if envPath.len > 0 and dirExists(envPath):
+    return envPath
+  # Check current directory's lib first (project-local libs)
+  let candidate0 = getCurrentDir() / "lib"
+  if dirExists(candidate0): return candidate0
   let appDir = getAppDir()
   let candidate1 = appDir / "lib"
   let candidate2 = appDir.parentDir / "lib"
-  let candidate3 = getCurrentDir() / "lib"
   if dirExists(candidate1): return candidate1
   if dirExists(candidate2): return candidate2
-  if dirExists(candidate3): return candidate3
   return "lib"
 
 proc resolveNsToPath(nsName: string, searchPaths: seq[string]): string =

src/deps.nim

@@ -17,6 +17,7 @@ type
 
   DepsFile* = object
     deps*: seq[Dependency]
+    paths*: seq[string]
 
   DepsError* = object of CatchableError
 
@@ -103,6 +104,11 @@ proc parseDepsFile*(filePath: string): DepsFile =
   for (pk, pv) in pairs:
     if pk == "deps":
       result.deps = parseDepsMap(pv)
+    elif pk == "paths":
+      if pv.kind == ckVector:
+        for p in pv.items:
+          if p.kind == ckString:
+            result.paths.add(p.strVal)
 
 proc depsDir*(projectDir: string): string =
   ## Return the .deps directory path for a project
@@ -139,6 +145,11 @@ proc gitCheckout*(repoDir, sha: string): bool =
 proc resolveDeps*(depsFile: DepsFile, projectDir: string): seq[string] =
   ## Download/resolve all dependencies and return search paths
   result = @[]
+  # Add :paths from deps.edn
+  for p in depsFile.paths:
+    let absPath = if p.isAbsolute: p else: projectDir / p
+    if dirExists(absPath):
+      result.add(absPath)
   for dep in depsFile.deps:
     case dep.kind
     of dkLocal:

src/emitter.nim

@@ -1,5 +1,5 @@
 # Bara Lang → Nim Emitter
-import strutils, sets, algorithm
+import strutils, sets, algorithm, sequtils
 import types
 import macros
 
@@ -9,6 +9,8 @@ var loopStack*: seq[seq[string]] = @[]
 var nsAliases*: seq[(string, string)] = @[]  # (alias, namespace)
 var scopeStack*: seq[HashSet[string]] = @[]
 var definedGlobals*: HashSet[string] = initHashSet[string]()
+var multiArityFns*: HashSet[string] = initHashSet[string]()
+var loopResultVar*: string = ""  # Set by loop handler when result capture is needed
 
 proc registerGlobal*(name: string) =
   definedGlobals.incl(name)
@@ -454,6 +456,12 @@ proc emitSpecialForm(items: seq[CljVal], indent: int): string =
   let sp = indentStr(indent)
   let head = items[0]
   if head.kind != ckSymbol:
+    # (:key map) — keyword as function: lookup key in map
+    if head.kind == ckKeyword:
+      if items.len == 2:
+        return sp & "cljGet(" & emitExpr(items[1], 0) & ", cljKeyword(\"" & head.kwName & "\"))"
+      elif items.len == 3:
+        return sp & "cljGetDefault(" & emitExpr(items[1], 0) & ", cljKeyword(\"" & head.kwName & "\"), " & emitExpr(items[2], 0) & ")"
     # Head is not a symbol - evaluate as function call: ((fn ...) args...)
     var argParts: seq[string] = @[]
     for i in 1..<items.len:
@@ -706,19 +714,112 @@ proc emitSpecialForm(items: seq[CljVal], indent: int): string =
     if name.kind != ckSymbol:
       raise newException(EmitterError, "defn name must be a symbol")
     registerGlobal(name.symName)
-    let params = items[2]
+    # Skip docstring if present: (defn name "doc" [params] body...)
+    var paramsIdx = 2
+    if items.len > 3 and items[2].kind == ckString:
+      paramsIdx = 3
+    let params = items[paramsIdx]
+    # Multi-arity defn: (defn name ([a] ...) ([a b] ...))
+    if params.kind == ckList:
+      let procName = mangleName(name.symName)
+      let exportMarker = if emitLibMode: "*" else: ""
+      # Register as multi-arity BEFORE emitting arity bodies (so internal calls wrap correctly)
+      multiArityFns.incl(name.symName)
+      var arityProcs: seq[string] = @[]
+      var dispatchCases: seq[string] = @[]
+      for arityIdx in paramsIdx..<items.len:
+        let arityForm = items[arityIdx]
+        if arityForm.kind == ckList and arityForm.items.len >= 2 and
+           arityForm.items[0].kind == ckVector:
+          let arityParams = arityForm.items[0]
+          let arityBody = arityForm.items[1..^1]
+          let paramCount = arityParams.items.len
+          var paramNames: seq[string] = @[]
+          pushScope()
+          for p in arityParams.items:
+            if p.kind != ckSymbol:
+              raise newException(EmitterError, "defn params must be symbols")
+            addToScope(p.symName)
+            paramNames.add(mangleName(p.symName) & ": CljVal")
+          var bodyCode = ""
+          if arityBody.len == 1:
+            bodyCode = emitExpr(arityBody[0], indent + 1)
+          else:
+            bodyCode = emitBlock(arityBody, indent + 1)
+          popScope()
+          let arityName = procName & "_arity" & $paramCount
+          arityProcs.add(sp & "proc " & arityName & "(" & paramNames.join(", ") & "): CljVal =\n" & bodyCode)
+          let argCall = (0..<paramCount).mapIt("args[" & $it & "]").join(", ")
+          dispatchCases.add(indentStr(indent + 1) & "of " & $paramCount & ": " & arityName & "(" & argCall & ")")
+      if arityProcs.len > 0:
+        var allLines: seq[string] = @[]
+        # Forward declaration for the dispatch proc
+        allLines.add(sp & "proc " & procName & exportMarker & "(args: seq[CljVal]): CljVal")
+        for ap in arityProcs:
+          allLines.add(ap)
+        allLines.add(sp & "proc " & procName & exportMarker & "(args: seq[CljVal]): CljVal =")
+        allLines.add(indentStr(indent + 1) & "case args.len")
+        for dc in dispatchCases:
+          allLines.add(dc)
+        allLines.add(indentStr(indent + 1) & "else: raise newException(CatchableError, \"Wrong number of args to " & name.symName & "\")")
+        # Register as multi-arity so call sites use cljApply
+        multiArityFns.incl(name.symName)
+        return allLines.join("\n")
     if params.kind != ckVector:
       raise newException(EmitterError, "defn params must be a vector")
     var paramNames: seq[string] = @[]
+    var hasRest = false
+    var restIdx = -1
     pushScope()
-    for p in params.items:
-      if p.kind != ckSymbol:
-        raise newException(EmitterError, "defn params must be symbols")
-      addToScope(p.symName)
-      paramNames.add(mangleName(p.symName) & ": CljVal")
-    let body = items[3..^1]
+    # First pass: check for & rest params
+    for pi, p in params.items:
+      if p.kind == ckSymbol and p.symName == "&":
+        hasRest = true
+        restIdx = pi
+        break
+    if hasRest:
+      # Collect named params before &
+      for pi in 0..<restIdx:
+        let p = params.items[pi]
+        if p.kind != ckSymbol:
+          raise newException(EmitterError, "defn params must be symbols")
+        addToScope(p.symName)
+      # The param after & is the rest param name
+      if restIdx + 1 < params.items.len:
+        let restParam = params.items[restIdx + 1]
+        if restParam.kind != ckSymbol:
+          raise newException(EmitterError, "defn rest param must be a symbol")
+        addToScope(restParam.symName)
+    else:
+      for p in params.items:
+        if p.kind != ckSymbol:
+          raise newException(EmitterError, "defn params must be symbols")
+        addToScope(p.symName)
+        paramNames.add(mangleName(p.symName) & ": CljVal")
+    let body = items[(paramsIdx+1)..^1]
     let procName = mangleName(name.symName)
     let exportMarker = if emitLibMode: "*" else: ""
+    if hasRest:
+      # Rest params: generate proc with args: seq[CljVal]
+      # Register so call sites wrap args in @[...]
+      multiArityFns.incl(name.symName)
+      let namedCount = restIdx
+      var preambleLines: seq[string] = @[]
+      for pi in 0..<restIdx:
+        let p = params.items[pi]
+        preambleLines.add(indentStr(indent + 1) & "let " & mangleName(p.symName) & " = args[" & $pi & "]")
+      let restParamName = params.items[restIdx + 1].symName
+      preambleLines.add(indentStr(indent + 1) & "let " & mangleName(restParamName) & " = cljList(args[" & $namedCount & "..^1])")
+      var bodyCode = ""
+      if body.len == 0:
+        bodyCode = indentStr(indent + 1) & "cljNil()"
+      elif body.len == 1:
+        bodyCode = emitExpr(body[0], indent + 1)
+      else:
+        bodyCode = emitBlock(body, indent + 1)
+      popScope()
+      let preamble = preambleLines.join("\n")
+      return sp & "proc " & procName & exportMarker & "(args: seq[CljVal]): CljVal =\n" & preamble & "\n" & bodyCode
     if indent == 0:
       var bodyCode = ""
       if body.len == 0:
@@ -751,17 +852,62 @@ proc emitSpecialForm(items: seq[CljVal], indent: int): string =
     if name.kind != ckSymbol:
       raise newException(EmitterError, "defn- name must be a symbol")
     registerGlobal(name.symName)
-    let params = items[2]
+    # Skip docstring if present: (defn- name "doc" [params] body...)
+    var paramsIdx = 2
+    if items.len > 3 and items[2].kind == ckString:
+      paramsIdx = 3
+    let params = items[paramsIdx]
     if params.kind != ckVector:
       raise newException(EmitterError, "defn- params must be a vector")
     var paramNames: seq[string] = @[]
+    var hasRest = false
+    var restIdx = -1
     pushScope()
-    for p in params.items:
-      if p.kind != ckSymbol:
-        raise newException(EmitterError, "defn- params must be symbols")
-      addToScope(p.symName)
-      paramNames.add(mangleName(p.symName) & ": CljVal")
-    let body = items[3..^1]
+    # First pass: check for & rest params
+    for pi, p in params.items:
+      if p.kind == ckSymbol and p.symName == "&":
+        hasRest = true
+        restIdx = pi
+        break
+    if hasRest:
+      for pi in 0..<restIdx:
+        let p = params.items[pi]
+        if p.kind != ckSymbol:
+          raise newException(EmitterError, "defn- params must be symbols")
+        addToScope(p.symName)
+      if restIdx + 1 < params.items.len:
+        let restParam = params.items[restIdx + 1]
+        if restParam.kind != ckSymbol:
+          raise newException(EmitterError, "defn- rest param must be a symbol")
+        addToScope(restParam.symName)
+    else:
+      for p in params.items:
+        if p.kind != ckSymbol:
+          raise newException(EmitterError, "defn- params must be symbols")
+        addToScope(p.symName)
+        paramNames.add(mangleName(p.symName) & ": CljVal")
+    let body = items[(paramsIdx+1)..^1]
+    let procName = mangleName(name.symName)
+    if hasRest:
+      # Rest params: generate proc with args: seq[CljVal]
+      multiArityFns.incl(name.symName)
+      let namedCount = restIdx
+      var preambleLines: seq[string] = @[]
+      for pi in 0..<restIdx:
+        let p = params.items[pi]
+        preambleLines.add(indentStr(indent + 1) & "let " & mangleName(p.symName) & " = args[" & $pi & "]")
+      let restParamName = params.items[restIdx + 1].symName
+      preambleLines.add(indentStr(indent + 1) & "let " & mangleName(restParamName) & " = cljList(args[" & $namedCount & "..^1])")
+      var bodyCode = ""
+      if body.len == 0:
+        bodyCode = indentStr(indent + 1) & "cljNil()"
+      elif body.len == 1:
+        bodyCode = emitExpr(body[0], indent + 1)
+      else:
+        bodyCode = emitBlock(body, indent + 1)
+      popScope()
+      let preamble = preambleLines.join("\n")
+      return sp & "proc " & procName & "(args: seq[CljVal]): CljVal {.used.} =\n" & preamble & "\n" & bodyCode
     var bodyCode = ""
     if body.len == 0:
       bodyCode = indentStr(indent + 1) & "cljNil()"
@@ -770,7 +916,6 @@ proc emitSpecialForm(items: seq[CljVal], indent: int): string =
     else:
       bodyCode = emitBlock(body, indent + 1)
     popScope()
-    let procName = mangleName(name.symName)
     return sp & "proc " & procName & "(" & paramNames.join(", ") & "): CljVal {.used.} =\n" & bodyCode
 
   of "fn":
@@ -909,12 +1054,53 @@ proc emitSpecialForm(items: seq[CljVal], indent: int): string =
   of "if":
     if items.len < 3 or items.len > 4:
       raise newException(EmitterError, "if requires condition, then, and optional else")
+    # Recursively check if an if form has control flow in any branch
+    proc ifHasControlFlow(form: CljVal): bool =
+      if form.kind != ckList or form.items.len < 3: return false
+      if form.items[0].kind != ckSymbol or form.items[0].symName != "if": return false
+      let thenCode = emitExpr(form.items[2], 0)
+      if thenCode.strip().contains("continue") or thenCode.strip().contains("break"):
+        return true
+      if form.items.len == 4:
+        let elseCode = emitExpr(form.items[3], 0)
+        if elseCode.strip().contains("continue") or elseCode.strip().contains("break"):
+          return true
+        # Recurse into nested if in else branch
+        if form.items[3].kind == ckList and form.items[3].items.len > 0 and
+           form.items[3].items[0].kind == ckSymbol and form.items[3].items[0].symName == "if":
+          return ifHasControlFlow(form.items[3])
+      return false
     let condCode = emitExpr(items[1], 0)
     let thenCode = emitExpr(items[2], indent + 1)
-    var ifBlock = sp & "if cljIsTruthy(" & condCode.strip() & "):\n" & thenCode
+    let thenStripped = thenCode.strip()
+    let thenIsControl = thenStripped.contains("continue") or thenStripped.contains("break")
+    let hasCF = ifHasControlFlow(items[0])
     if items.len == 4:
       let elseCode = emitExpr(items[3], indent + 1)
+      let elseStripped = elseCode.strip()
+      let elseIsControl = elseStripped.contains("continue") or elseStripped.contains("break")
+      if thenIsControl or elseIsControl:
+        # Direct control flow in branches — use statement form
+        var lines: seq[string] = @[]
+        lines.add(sp & "if cljIsTruthy(" & condCode.strip() & "):")
+        if thenIsControl:
+          lines.add(thenCode)
+        elif loopResultVar.len > 0:
+          lines.add(indentStr(indent + 1) & loopResultVar & " = " & thenStripped)
+        else:
+          lines.add(indentStr(indent + 1) & "discard " & thenStripped)
+        lines.add(sp & "else:")
+        if elseIsControl:
+          lines.add(elseCode)
+        elif loopResultVar.len > 0:
+          lines.add(indentStr(indent + 1) & loopResultVar & " = " & elseStripped)
+        else:
+          lines.add(indentStr(indent + 1) & "discard " & elseStripped)
+        return lines.join("\n")
+      var ifBlock = sp & "if cljIsTruthy(" & condCode.strip() & "):\n" & thenCode
       ifBlock.add("\n" & sp & "else:\n" & elseCode)
+      return ifBlock
+    var ifBlock = sp & "if cljIsTruthy(" & condCode.strip() & "):\n" & thenCode
     return ifBlock
 
   of "when":
@@ -999,21 +1185,43 @@ proc emitSpecialForm(items: seq[CljVal], indent: int): string =
       lines.add(sp & "var " & lpName & ": CljVal = " & lpVal)
       loopVars.add(lpName)
     loopStack.add(loopVars)
-    lines.add(sp & "while true:")
     let body = items[2..^1]
+    # Check if the last form is an 'if' with control flow in branches (recursively)
+    proc ifHasCF(form: CljVal): bool =
+      if form.kind != ckList or form.items.len < 3: return false
+      if form.items[0].kind != ckSymbol or form.items[0].symName != "if": return false
+      let thenCode = emitExpr(form.items[2], 0)
+      if thenCode.strip().contains("continue") or thenCode.strip().contains("break"):
+        return true
+      if form.items.len == 4:
+        let elseCode = emitExpr(form.items[3], 0)
+        if elseCode.strip().contains("continue") or elseCode.strip().contains("break"):
+          return true
+        if form.items[3].kind == ckList and form.items[3].items.len > 0 and
+           form.items[3].items[0].kind == ckSymbol and form.items[3].items[0].symName == "if":
+          return ifHasCF(form.items[3])
+      return false
+    var needsResultVar = false
+    if body.len > 0:
+      needsResultVar = ifHasCF(body[^1])
+    if needsResultVar:
+      lines.add(sp & "var loopResult: CljVal = cljNil()")
+      loopResultVar = "loopResult"
+    lines.add(sp & "while true:")
     for bi, b in body:
       let bcode = emitExpr(b, indent + 1)
       let stripped = bcode.strip()
       let isLast = (bi == body.len - 1)
-      let isStatement = stripped.startsWith("echo ") or stripped.startsWith("discard ") or
-                        stripped.startsWith("var ") or stripped.startsWith("let ") or
-                        stripped.startsWith("proc ") or
-                        stripped.startsWith("if ") or stripped.startsWith("try:") or
-                        stripped.startsWith("while ") or stripped.contains("continue")
-      if isLast or isStatement:
+      if isLast and needsResultVar:
+        # Last form with control flow: the if handler uses loopResultVar
+        lines.add(bcode)
+      elif isLast or stripped.startsWith("echo ") or stripped.startsWith("discard ") or
+         stripped.startsWith("var ") or stripped.startsWith("let ") or
+         stripped.startsWith("proc ") or
+         stripped.startsWith("if ") or stripped.startsWith("try:") or
+         stripped.startsWith("while ") or stripped.contains("continue"):
         lines.add(bcode)
       elif stripped.startsWith("block:"):
-        # Multi-line block as non-last form: discard the last line
         var blockLines = bcode.split("\n")
         var lastIdx = blockLines.len - 1
         while lastIdx >= 0 and blockLines[lastIdx].strip() == "":
@@ -1029,6 +1237,9 @@ proc emitSpecialForm(items: seq[CljVal], indent: int): string =
     lines.add(indentStr(indent + 1) & "break")
     discard loopStack.pop()
     popScope()
+    if needsResultVar:
+      lines.add(sp & "loopResult")
+      loopResultVar = ""
     return lines.join("\n")
 
   of "recur":
@@ -1737,7 +1948,11 @@ proc emitSpecialForm(items: seq[CljVal], indent: int): string =
       let parts = op.replace(".", "/").split("/")
       if parts.len >= 3:
         let module = parts[1]
-        var funcChain = parts[2..^1].join(".")
+        # Mangle each part of the function chain for Nim identifier validity
+        var mangledParts: seq[string] = @[]
+        for p in parts[2..^1]:
+          mangledParts.add(mangleName(p))
+        var funcChain = mangledParts.join(".")
         # Strip ? suffix (Clojure convention) — not valid in Nim
         if funcChain.endsWith("?"):
           funcChain = funcChain[0..^2]
@@ -1867,6 +2082,9 @@ proc emitSpecialForm(items: seq[CljVal], indent: int): string =
     if callOp.endsWith("."):
       callOp = callOp[0..^2]
     let mangled = mangleName(callOp)
+    # Multi-arity function: wrap args in seq
+    if callOp in multiArityFns:
+      return sp & mangled & "(@[" & args.join(", ") & "])"
     if isLocalVar(callOp):
       # Local value (may be fn, map, set, vector, keyword) — use runtime dispatch
       return sp & "cljCall(" & mangled & ", @[" & args.join(", ") & "])"
@@ -2141,9 +2359,14 @@ proc emitProgramInternal(forms: seq[CljVal]): string =
 
   if mainForms.len > 0:
     lines.add("")
-    lines.add("when isMainModule:")
-    for form in mainForms:
-      lines.add(form)
+    if emitLibMode:
+      # Lib mode: emit main forms at top level (no when isMainModule guard)
+      for form in mainForms:
+        lines.add(form)
+    else:
+      lines.add("when isMainModule:")
+      for form in mainForms:
+        lines.add(form)
 
   return lines.join("\n") & "\n"