Nim: step9

4 files changed, 373 insertions, 17 deletions

diff --git a/nim/core.nim b/nim/core.nim
index 0951f92..ca25802 100644
--- a/nim/core.nim
+++ b/nim/core.nim
@@ -1,4 +1,7 @@
-import strutils, types, printer, reader
+import strutils, rdstdin, tables, algorithm, types, printer, reader
+
+type MalError* = object of Exception
+  t*: MalType
 
 # String functions
 proc pr_str(xs: varargs[MalType]): MalType =
@@ -19,6 +22,9 @@ proc println(xs: varargs[MalType]): MalType =
 proc read_str(xs: varargs[MalType]): MalType =
   read_str(xs[0].str)
 
+proc readline(xs: varargs[MalType]): MalType =
+  str readLineFromStdin(xs[0].str)
+
 proc slurp(xs: varargs[MalType]): MalType =
   str readFile(xs[0].str)
 
@@ -44,8 +50,90 @@ proc rest(xs: varargs[MalType]): MalType =
   if xs[0].list.len > 0: list xs[0].list[1 .. -1]
   else: list()
 
+proc throw(xs: varargs[MalType]): MalType =
+  raise (ref MalError)(t: list xs)
+
+proc assoc(xs: varargs[MalType]): MalType =
+  result.deepCopy xs[0]
+  for i in countup(1, xs.high, 2):
+    result.hash_map[xs[i].str] = xs[i+1]
+
+proc dissoc(xs: varargs[MalType]): MalType =
+  result.deepCopy xs[0]
+  for i in 1 .. xs.high:
+    if result.hash_map.hasKey(xs[i].str): result.hash_map.del(xs[i].str)
+
+proc get(xs: varargs[MalType]): MalType =
+  if xs[0].kind == HashMap:
+    xs[0].hash_map[xs[1].str]
+  else:
+    nilObj
+
+proc contains_q(xs: varargs[MalType]): MalType =
+  boolObj xs[0].hash_map.hasKey(xs[1].str)
+
+proc keys(xs: varargs[MalType]): MalType =
+  result = list()
+  for key in xs[0].hash_map.keys:
+    result.list.add str(key)
+
+proc vals(xs: varargs[MalType]): MalType =
+  result = list()
+  for value in xs[0].hash_map.values:
+    result.list.add value
+
+proc conj(xs: varargs[MalType]): MalType =
+  if xs[0].kind == List:
+    result = list()
+    for i in countdown(xs.high, 1):
+      result.list.add xs[i]
+    result.list.add xs[0].list
+  else:
+    result = vector()
+    result.list.add xs[0].list
+    for i in 1..xs.high:
+      result.list.add xs[i]
+  result.meta = xs[0].meta
+
+proc apply(xs: varargs[MalType]): MalType =
+  var s = newSeq[MalType]()
+  if xs.len > 2:
+    for j in 1 .. xs.high-1:
+      s.add xs[j]
+  s.add xs[xs.high].list
+  xs[0].getFun()(s)
+
+proc map(xs: varargs[MalType]): MalType =
+  result = list()
+  for i in 0 .. xs[1].list.high:
+    result.list.add xs[0].getFun()(xs[1].list[i])
+
+proc with_meta(xs: varargs[MalType]): MalType =
+  result = xs[0]
+  new result.meta
+  result.meta[] = xs[1]
+
+proc meta(xs: varargs[MalType]): MalType =
+  if xs[0].meta != nil: xs[0].meta[]
+  else: nilObj
+
+proc deref(xs: varargs[MalType]): MalType =
+  xs[0].val[]
+
+proc reset_bang(xs: varargs[MalType]): MalType =
+  xs[0].val[] = xs[1]
+  result = xs[0].val[]
+
+proc swap_bang(xs: varargs[MalType]): MalType =
+  var args = @[xs[0].val[]]
+  for i in 2 .. xs.high:
+    args.add xs[i]
+  xs[0].val[] = xs[1].getFun()(args)
+  result = xs[0].val[]
+
 template wrapNumberFun(op: expr): expr =
-  fun proc(xs: varargs[MalType]): MalType = number op(xs[0].number, xs[1].number)
+  fun proc(xs: varargs[MalType]): MalType =
+    number op(xs[0].number, xs[1].number)
 
 template wrapBoolFun(op: expr): expr =
   fun proc(xs: varargs[MalType]): MalType =
@@ -66,10 +154,16 @@ let ns* = {
   "list?": fun list_q,
   "vector": fun vector,
   "vector?": fun vector_q,
-  "hash_map": fun hash_map,
-  "hash_map?": fun hash_map_q,
+  "hash-map": fun hash_map,
+  "map?": fun hash_map_q,
   "empty?": fun empty_q,
-  "count": fun count,
+  "assoc": fun assoc,
+  "dissoc": fun dissoc,
+  "get": fun get,
+  "contains?": fun contains_q,
+  "keys": fun keys,
+  "vals": fun vals,
+
   "=": fun equal,
 
   "pr-str": fun pr_str,
@@ -78,11 +172,35 @@ let ns* = {
   "println": fun println,
 
   "read-string": fun read_str,
+  "readline": fun readline,
   "slurp": fun slurp,
+
+  "sequential?": fun seq_q,
   "cons": fun cons,
   "concat": fun concat,
-
+  "count": fun count,
   "nth": fun nth,
   "first": fun first,
   "rest": fun rest,
+  "conj": fun conj,
+  "apply": fun apply,
+  "map": fun map,
+
+  "throw": fun throw,
+
+  "nil?": fun nil_q,
+  "true?": fun true_q,
+  "false?": fun false_q,
+  "symbol": fun symbol,
+  "symbol?": fun symbol_q,
+  "keyword": fun keyword,
+  "keyword?": fun keyword_q,
+
+  "with-meta": fun with_meta,
+  "meta": fun meta,
+  "atom": fun atom,
+  "atom?": fun atom_q,
+  "deref": fun deref,
+  "reset!": fun reset_bang,
+  "swap!": fun swap_bang,
 }
diff --git a/nim/printer.nim b/nim/printer.nim
index eb26671..b6bf4c7 100644
--- a/nim/printer.nim
+++ b/nim/printer.nim
@@ -1,5 +1,11 @@
 import strutils, sequtils, tables, types
 
+proc str_handle(x: string, pr = true): string =
+  if x.len > 0 and x[0] == '\xff':
+            result = ":" & x[1 .. x.high]
+  elif pr:  result = "\"" & x.replace("\"", "\\\"") & "\""
+  else:     result = x
+
 proc pr_str*(m: MalType, pr = true): string =
   case m.kind
   of Nil:     result = "nil"
@@ -7,12 +13,9 @@ proc pr_str*(m: MalType, pr = true): string =
   of False:   result = "false"
   of Fun:     result = "#<function>"
   of MalFun:  result = "#<malfun>"
+  of Atom:    result = "(atom " & m.val[].pr_str & ")"
   of Symbol:  result = m.str
-  of String:
-    if m.str.len > 0 and m.str[0] == '\xff':
-              result = ":" & m.str[1 .. m.str.high]
-    elif pr:  result = "\"" & m.str.replace("\"", "\\\"") & "\""
-    else:     result = m.str
+  of String:  result = m.str.str_handle(pr)
   of Number:  result = $m.number
   of List:    result = "(" & m.list.mapIt(string, it.pr_str(pr)).join(" ") & ")"
   of Vector:  result = "[" & m.list.mapIt(string, it.pr_str(pr)).join(" ") & "]"
@@ -20,5 +23,5 @@ proc pr_str*(m: MalType, pr = true): string =
     result = "{"
     for key, val in m.hash_map.pairs:
       if result.len > 1: result.add " "
-      result.add key & " " & val.pr_str(pr)
+      result.add key.str_handle & " " & val.pr_str(pr)
     result.add "}"
diff --git a/nim/step9_try.nim b/nim/step9_try.nim
new file mode 100644
index 0000000..688817d
--- /dev/null
+++ b/nim/step9_try.nim
@@ -0,0 +1,190 @@
+import rdstdin, tables, sequtils, os, types, reader, printer, env, core
+
+proc read(str: string): MalType = str.read_str
+
+proc is_pair(x: MalType): bool =
+  x.kind in {List, Vector} and x.list.len > 0
+
+proc quasiquote(ast: MalType): MalType =
+  if not ast.is_pair:
+    return list(symbol "quote", ast)
+  elif ast.list[0] == symbol "unquote":
+    return ast.list[1]
+  elif ast.list[0].is_pair and ast.list[0].list[0] == symbol "splice-unquote":
+    return list(symbol "concat", ast.list[0].list[1],
+      quasiquote(list ast.list[1 .. -1]))
+  else:
+    return list(symbol "cons", quasiquote(ast.list[0]), quasiquote(list(ast.list[1 .. -1])))
+
+proc is_macro_call(ast: MalType, env: Env): bool =
+  ast.kind == List and ast.list[0].kind == Symbol and
+    env.find(ast.list[0].str) != nil and env.get(ast.list[0].str).macro_q
+
+proc macroexpand(ast: MalType, env: Env): MalType =
+  result = ast
+  while result.is_macro_call(env):
+    let mac = env.get(result.list[0].str)
+    result = mac.malfun.fn(result.list[1 .. -1]).macroexpand(env)
+
+proc eval(ast: MalType, env: Env): MalType
+
+proc eval_ast(ast: MalType, env: var Env): MalType =
+  case ast.kind
+  of Symbol:
+    result = env.get(ast.str)
+  of List:
+    result = list ast.list.mapIt(MalType, it.eval(env))
+  of Vector:
+    result = vector ast.list.mapIt(MalType, it.eval(env))
+  of HashMap:
+    result = hash_map()
+    for k, v in ast.hash_map.pairs:
+      result.hash_map[k] = v.eval(env)
+  else:
+    result = ast
+
+proc eval(ast: MalType, env: Env): MalType =
+  var ast = ast
+  var env = env
+
+  template defaultApply =
+    let el = ast.eval_ast(env)
+    let f = el.list[0]
+    case f.kind
+    of MalFun:
+      ast = f.malfun.ast
+      env = initEnv(f.malfun.env, f.malfun.params, list(el.list[1 .. -1]))
+    else:
+      return f.fun(el.list[1 .. -1])
+
+  while true:
+    if ast.kind != List: return ast.eval_ast(env)
+
+    ast = ast.macroexpand(env)
+    if ast.kind != List: return ast
+    if ast.list.len == 0: return ast
+
+    let a0 = ast.list[0]
+    case a0.kind
+    of Symbol:
+      case a0.str
+      of "def!":
+        let
+          a1 = ast.list[1]
+          a2 = ast.list[2]
+          res = a2.eval(env)
+        return env.set(a1.str, res)
+
+      of "let*":
+        let
+          a1 = ast.list[1]
+          a2 = ast.list[2]
+        var let_env = Env(env)
+        case a1.kind
+        of List, Vector:
+          for i in countup(0, a1.list.high, 2):
+            let_env.set(a1.list[i].str, a1.list[i+1].eval(let_env))
+        else: raise newException(ValueError, "Illegal kind in let*")
+        ast = a2
+        env = let_env
+        # Continue loop (TCO)
+
+      of "quote":
+        return ast.list[1]
+
+      of "quasiquote":
+        ast = ast.list[1].quasiquote
+        # Continue loop (TCO)
+
+      of "defmacro!":
+        var fun = ast.list[2].eval(env)
+        fun.malfun.is_macro = true
+        return env.set(ast.list[1].str, fun)
+
+      of "macroexpand":
+        return ast.list[1].macroexpand(env)
+
+      of "try*":
+        let
+          a1 = ast.list[1]
+          a2 = ast.list[2]
+        if a2.list[0].str == "catch*":
+          try:
+            return a1.eval(env)
+          except MalError:
+            let exc = (ref MalError) getCurrentException()
+            var catchEnv = initEnv(env, list a2.list[1], exc.t)
+            return a2.list[2].eval(catchEnv)
+          except:
+            let exc = getCurrentExceptionMsg()
+            var catchEnv = initEnv(env, list a2.list[1], list str(exc))
+            return a2.list[2].eval(catchEnv)
+        else:
+          return a1.eval(env)
+
+      of "do":
+        let last = ast.list.high
+        let el = (list ast.list[1 .. <last]).eval_ast(env)
+        ast = ast.list[last].eval(env)
+        # Continue loop (TCO)
+
+      of "if":
+        let
+          a1 = ast.list[1]
+          a2 = ast.list[2]
+          cond = a1.eval(env)
+
+        if cond.kind in {Nil, False}:
+          if ast.list.len > 3: ast = ast.list[3]
+          else: ast = nilObj
+        else: ast = a2
+
+      of "fn*":
+        let
+          a1 = ast.list[1]
+          a2 = ast.list[2]
+        var env2 = env
+        let fn = proc(a: varargs[MalType]): MalType =
+          var newEnv = initEnv(env2, a1, list(a))
+          a2.eval(newEnv)
+        return malfun(fn, a2, a1, env)
+
+      else:
+        defaultApply()
+
+    else:
+      defaultApply()
+
+proc print(exp: MalType): string = exp.pr_str
+
+var repl_env = initEnv()
+
+for k, v in ns.items:
+  repl_env.set(k, v)
+repl_env.set("eval", fun(proc(xs: varargs[MalType]): MalType = eval(xs[0], repl_env)))
+var ps = commandLineParams()
+repl_env.set("*ARGV*", list((if paramCount() > 1: ps[1..ps.high] else: @[]).map(str)))
+
+
+# core.nim: defined using nim
+proc rep(str: string): string {.discardable.} =
+  str.read.eval(repl_env).print
+
+# core.mal: defined using mal itself
+rep "(def! not (fn* (a) (if a false true)))"
+rep "(def! load-file (fn* (f) (eval (read-string (str \"(do \" (slurp f) \")\")))))"
+rep "(defmacro! cond (fn* (& xs) (if (> (count xs) 0) (list 'if (first xs) (if (> (count xs) 1) (nth xs 1) (throw \"odd number of forms to cond\")) (cons 'cond (rest (rest xs)))))))"
+rep "(defmacro! or (fn* (& xs) (if (empty? xs) nil (if (= 1 (count xs)) (first xs) `(let* (or_FIXME ~(first xs)) (if or_FIXME or_FIXME (or ~@(rest xs))))))))"
+
+if paramCount() >= 1:
+  rep "(load-file \"" & paramStr(1) & "\")"
+  quit()
+
+while true:
+  try:
+    let line = readLineFromStdin("user> ")
+    echo line.rep
+  except Blank: discard
+  except:
+    echo getCurrentExceptionMsg()
+    echo getCurrentException().getStackTrace()
diff --git a/nim/types.nim b/nim/types.nim
index 9936d50..2a19eba 100644
--- a/nim/types.nim
+++ b/nim/types.nim
@@ -2,10 +2,12 @@ import tables, strutils
 
 type
   MalTypeKind* = enum Nil, True, False, Number, Symbol, String,
-    List, Vector, HashMap, Fun, MalFun
+    List, Vector, HashMap, Fun, MalFun, Atom
+
+  FunType = proc(a: varargs[MalType]): MalType
 
   MalFunType* = ref object
-    fn*:       proc(a: varargs[MalType]): MalType
+    fn*:       FunType
     ast*:      MalType
     params*:   MalType
     env*:      Env
@@ -19,9 +21,12 @@ type
     of List, Vector:     list*:     seq[MalType]
     of HashMap:          hash_map*: TableRef[string, MalType]
     of Fun:
-                         fun*:      proc(xs: varargs[MalType]): MalType
+                         fun*:      FunType
                          is_macro*: bool
     of MalFun:           malfun*:   MalFunType
+    of Atom:             val*:      ref MalType
+
+    meta*: ref MalType
 
   Env* = ref object
     data*: Table[string, MalType]
@@ -40,6 +45,11 @@ proc str*(x: string): MalType {.procvar.} = MalType(kind: String, str: x)
 
 proc keyword*(x: string): MalType = MalType(kind: String, str: "\xff" & x)
 
+proc atom*(x: MalType): MalType =
+  result = MalType(kind: Atom)
+  new result.val
+  result.val[] = x
+
 proc list*(xs: varargs[MalType]): MalType {.procvar.} =
   result = MalType(kind: List, list: @[])
   for x in xs: result.list.add x
@@ -52,7 +62,7 @@ proc hash_map*(xs: varargs[MalType]): MalType {.procvar.} =
   result = MalType(kind: HashMap, hash_map: newTable[string, MalType]())
   for i in countup(0, xs.high, 2):
     let s = case xs[i].kind
-    of String: "\"" & xs[i].str & "\""
+    of String: xs[i].str
     else: xs[i].str
     result.hash_map[s] = xs[i+1]
 
@@ -60,6 +70,10 @@ proc macro_q*(x: MalType): bool =
   if x.kind == Fun: x.is_macro
   else: x.malfun.is_macro
 
+proc getFun*(x: MalType): FunType =
+  if x.kind == Fun: x.fun
+  else: x.malfun.fn
+
 proc fun*(x: proc(xs: varargs[MalType]): MalType, is_macro = false): MalType =
   MalType(kind: Fun, fun: x, is_macro: is_macro)
 
@@ -68,7 +82,7 @@ proc malfun*(fn: auto, ast, params: MalType,
   MalType(kind: MalFun, malfun: MalFunType(fn: fn, ast: ast, params: params,
     env: env, is_macro: is_macro))
 
-proc boolObj(b: bool): MalType =
+proc boolObj*(b: bool): MalType =
   if b: trueObj else: falseObj
 
 proc list_q*(xs: varargs[MalType]): MalType {.procvar.} =
@@ -77,12 +91,42 @@ proc list_q*(xs: varargs[MalType]): MalType {.procvar.} =
 proc vector_q*(xs: varargs[MalType]): MalType {.procvar.} =
   boolObj xs[0].kind == Vector
 
+proc seq_q*(xs: varargs[MalType]): MalType {.procvar.} =
+  boolObj xs[0].kind in {List, Vector}
+
 proc hash_map_q*(xs: varargs[MalType]): MalType {.procvar.} =
   boolObj xs[0].kind == HashMap
 
 proc empty_q*(xs: varargs[MalType]): MalType {.procvar.} =
   boolObj xs[0].list.len == 0
 
+proc nil_q*(xs: varargs[MalType]): MalType {.procvar.} =
+  boolObj xs[0].kind == Nil
+
+proc true_q*(xs: varargs[MalType]): MalType {.procvar.} =
+  boolObj xs[0].kind == True
+
+proc false_q*(xs: varargs[MalType]): MalType {.procvar.} =
+  boolObj xs[0].kind == False
+
+proc symbol*(xs: varargs[MalType]): MalType {.procvar.} =
+  symbol(xs[0].str)
+
+proc symbol_q*(xs: varargs[MalType]): MalType {.procvar.} =
+  boolObj xs[0].kind == Symbol
+
+proc keyword*(xs: varargs[MalType]): MalType {.procvar.} =
+  keyword(xs[0].str)
+
+proc keyword_q*(xs: varargs[MalType]): MalType {.procvar.} =
+  boolObj(xs[0].kind == String and xs[0].str[0] == '\xff')
+
+proc atom*(xs: varargs[MalType]): MalType {.procvar.} =
+  atom(xs[0])
+
+proc atom_q*(xs: varargs[MalType]): MalType {.procvar.} =
+  boolObj xs[0].kind == Atom
+
 proc count*(xs: varargs[MalType]): MalType {.procvar.} =
   number if xs[0].kind == Nil: 0 else: xs[0].list.len
 
@@ -97,6 +141,7 @@ proc `==`*(x, y: MalType): bool =
   of HashMap:        x.hash_map == y.hash_map
   of Fun:            x.fun      == y.fun
   of MalFun:         x.malfun   == y.malfun
+  of Atom:           x.val      == y.val
 
 proc equal*(xs: varargs[MalType]): MalType {.procvar.} =
   boolObj xs[0] == xs[1]