NEW LL(1) PARSER

1 files changed, 1332 insertions, 0 deletions

diff --git a/lparser.c b/lparser.c
new file mode 100644
index 00000000..0eefb204
--- /dev/null
+++ b/lparser.c
@@ -0,0 +1,1332 @@
+/*
+** $Id: $
+** LL(1) Parser and code generator for Lua
+** See Copyright Notice in lua.h
+*/
+
+
+#include <stdio.h>
+
+#include "lauxlib.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "llex.h"
+#include "lmem.h"
+#include "lopcodes.h"
+#include "lparser.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "lua.h"
+#include "luadebug.h"
+#include "lzio.h"
+
+
+/* for limit numbers in error messages */
+#define MES_LIM(x)      "(limit=" x ")"
+
+
+/* size of a "normal" jump instruction: OpCode + 1 byte */
+#define JMPSIZE 2
+
+/* maximum number of local variables */
+#define MAXLOCALS 32
+#define SMAXLOCALS "32"
+
+
+/* maximum number of upvalues */
+#define MAXUPVALUES 16
+#define SMAXUPVALUES "16"
+
+
+/*
+** Variable descriptor:
+** must include a "exp" option because LL(1) cannot distinguish
+** between variables, upvalues and function calls on first sight.
+** VGLOBAL: info is constant index of global name
+** VLOCAL: info is stack index
+** VDOT: info is constant index of index name
+** VEXP: info is pc index of "nparam" of function call (or 0 if exp is closed)
+*/
+typedef enum {VGLOBAL, VLOCAL, VDOT, VINDEXED, VEXP} varkind;
+
+typedef struct {
+  varkind k;
+  int info;
+} vardesc;
+
+
+/*
+** Expression List descriptor:
+** tells number of expressions in the list,
+** and, if last expression is open (a function call),
+** where is its pc index of "nparam"
+*/
+typedef struct {
+  int n;
+  int pc;  /* 0 if last expression is closed */
+} listdesc;
+
+
+/*
+** Constructors descriptor:
+** "n" indicates number of elements, and "k" signals whether
+** it is a list constructor (k = 0) or a record constructor (k = 1)
+** or empty (k = ';' or '}')
+*/
+typedef struct {
+  int n;
+  int k;
+} constdesc;
+
+
+/* state needed to generate code for a given function */
+typedef struct FuncState {
+  TProtoFunc *f;  /* current function header */
+  struct FuncState *prev;  /* enclosuring function */
+  int pc;  /* next position to code */
+  int stacksize;  /* number of values on activation register */
+  int maxstacksize;  /* maximum number of values on activation register */
+  int nlocalvar;  /* number of active local variables */
+  int nupvalues;  /* number of upvalues */
+  int nvars;  /* number of entries in f->locvars */
+  int maxcode;  /* size of f->code */
+  int maxvars;  /* size of f->locvars (-1 if no debug information) */
+  int maxconsts;  /* size of f->consts */
+  int lastsetline;  /* line where last SETLINE was issued */
+  vardesc upvalues[MAXUPVALUES];  /* upvalues */
+  TaggedString *localvar[MAXLOCALS];  /* store local variable names */
+} FuncState;
+
+
+static int assignment (LexState *ls, vardesc *v, int nvars);
+static int cond (LexState *ls);
+static int funcname (LexState *ls, vardesc *v);
+static int funcparams (LexState *ls, int slf);
+static int listfields (LexState *ls);
+static int localnamelist (LexState *ls);
+static int optional (LexState *ls, int c);
+static int recfields (LexState *ls);
+static int stat (LexState *ls);
+static void block (LexState *ls);
+static void body (LexState *ls, int needself, int line);
+static void chunk (LexState *ls);
+static void constructor (LexState *ls);
+static void decinit (LexState *ls, listdesc *d);
+static void exp (LexState *ls, vardesc *v);
+static void exp1 (LexState *ls);
+static void exp2 (LexState *ls, vardesc *v);
+static void explist (LexState *ls, listdesc *e);
+static void explist1 (LexState *ls, listdesc *e);
+static void ifpart (LexState *ls);
+static void parlist (LexState *ls);
+static void part (LexState *ls, constdesc *cd);
+static void recfield (LexState *ls);
+static void ret (LexState *ls);
+static void simpleexp (LexState *ls, vardesc *v);
+static void statlist (LexState *ls);
+static void var_or_func (LexState *ls, vardesc *v);
+static void var_or_func_tail (LexState *ls, vardesc *v);
+
+
+
+static void check_pc (FuncState *fs, int n) {
+  if (fs->pc+n > fs->maxcode)
+    fs->maxcode = luaM_growvector(&fs->f->code, fs->maxcode,
+                                  Byte, codeEM, MAX_INT);
+}
+
+
+static void code_byte (FuncState *fs, Byte c) {
+  check_pc(fs, 1);
+  fs->f->code[fs->pc++] = c;
+}
+
+
+static void deltastack (LexState *ls, int delta) {
+  FuncState *fs = ls->fs;
+  fs->stacksize += delta;
+  if (fs->stacksize > fs->maxstacksize) {
+    if (fs->stacksize > 255)
+      luaX_error(ls, "function/expression too complex");
+    fs->maxstacksize = fs->stacksize;
+  }
+}
+
+
+static int code_oparg_at (LexState *ls, int pc, OpCode op, int builtin,
+                          int arg, int delta) {
+  Byte *code = ls->fs->f->code;
+  deltastack(ls, delta);
+  if (arg < builtin) {
+    code[pc] = op+1+arg;
+    return 1;
+  }
+  else if (arg <= 255) {
+    code[pc] = op;
+    code[pc+1] = arg;
+    return 2;
+  }
+  else if (arg <= MAX_WORD) {
+    code[pc] = op+1+builtin;
+    code[pc+1] = arg>>8;
+    code[pc+2] = arg&0xFF;
+    return 3;
+  }
+  else luaX_error(ls, "code too long " MES_LIM("64K"));
+  return 0;   /* to avoid warnings */
+}
+
+
+static int fix_opcode (LexState *ls, int pc, OpCode op, int builtin, int arg) {
+  FuncState *fs = ls->fs;
+  TProtoFunc *f = fs->f;
+  if (arg < builtin) {  /* close space */
+    luaO_memdown(f->code+pc+1, f->code+pc+2, fs->pc-(pc+2));
+    fs->pc--;
+  }
+  else if (arg > 255) {  /* open space */
+    check_pc(fs, 1);
+    luaO_memup(f->code+pc+1, f->code+pc, fs->pc-pc);
+    fs->pc++;
+  }
+  return code_oparg_at(ls, pc, op, builtin, arg, 0) - 2;
+}
+
+static void code_oparg (LexState *ls, OpCode op, int builtin, int arg,
+                        int delta) {
+  check_pc(ls->fs, 3);  /* maximum code size */
+  ls->fs->pc += code_oparg_at(ls, ls->fs->pc, op, builtin, arg, delta);
+}
+
+
+static void code_opcode (LexState *ls, OpCode op, int delta) {
+  deltastack(ls, delta);
+  code_byte(ls->fs, op);
+}
+
+
+static void code_constant (LexState *ls, int c) {
+  code_oparg(ls, PUSHCONSTANT, 8, c, 1);
+}
+
+
+static int next_constant (FuncState *fs) {
+  TProtoFunc *f = fs->f;
+  if (f->nconsts >= fs->maxconsts) {
+    fs->maxconsts = luaM_growvector(&f->consts, fs->maxconsts, TObject,
+                                    constantEM, MAX_WORD);
+  }
+  return f->nconsts++;
+}
+
+
+static int string_constant (FuncState *fs, TaggedString *s) {
+  TProtoFunc *f = fs->f;
+  int c = s->constindex;
+  if (!(c < f->nconsts &&
+      ttype(&f->consts[c]) == LUA_T_STRING && tsvalue(&f->consts[c]) == s)) {
+    c = next_constant(fs);
+    ttype(&f->consts[c]) = LUA_T_STRING;
+    tsvalue(&f->consts[c]) = s;
+    s->constindex = c;  /* hint for next time */
+  }
+  return c;
+}
+
+
+static void code_string (LexState *ls, TaggedString *s) {
+  code_constant(ls, string_constant(ls->fs, s));
+}
+
+
+#define LIM 20
+static int real_constant (FuncState *fs, real r) {
+  /* check whether 'r' has appeared within the last LIM entries */
+  TObject *cnt = fs->f->consts;
+  int c = fs->f->nconsts;
+  int lim = c < LIM ? 0 : c-LIM;
+  while (--c >= lim) {
+    if (ttype(&cnt[c]) == LUA_T_NUMBER && nvalue(&cnt[c]) == r)
+      return c;
+  }
+  /* not found; create a luaM_new entry */
+  c = next_constant(fs);
+  cnt = fs->f->consts;  /* 'next_constant' may reallocate this vector */
+  ttype(&cnt[c]) = LUA_T_NUMBER;
+  nvalue(&cnt[c]) = r;
+  return c;
+}
+
+
+static void code_number (LexState *ls, real f) {
+  int i;
+  if (f >= 0 && f <= (real)MAX_WORD && (real)(i=(int)f) == f)
+    code_oparg(ls, PUSHNUMBER, 3, i, 1);  /* f has a short integer value */
+  else
+    code_constant(ls, real_constant(ls->fs, f));
+}
+
+
+static void flush_record (LexState *ls, int n) {
+  if (n > 0)
+    code_oparg(ls, SETMAP, 1, n-1, -2*n);
+}
+
+
+static void flush_list (LexState *ls, int m, int n) {
+  if (n == 0) return;
+  code_oparg(ls, SETLIST, 1, m, -n);
+  code_byte(ls->fs, n);
+}
+
+
+static void luaI_registerlocalvar (FuncState *fs, TaggedString *varname,
+                                   int line) {
+  if (fs->maxvars != -1) {  /* debug information? */
+    TProtoFunc *f = fs->f;
+    if (fs->nvars >= fs->maxvars)
+      fs->maxvars = luaM_growvector(&f->locvars, fs->maxvars,
+                                    LocVar, "", MAX_WORD);
+    f->locvars[fs->nvars].varname = varname;
+    f->locvars[fs->nvars].line = line;
+    fs->nvars++;
+  }
+}
+
+
+static void luaI_unregisterlocalvar (FuncState *fs, int line) {
+  luaI_registerlocalvar(fs, NULL, line);
+}
+
+
+static void store_localvar (LexState *ls, TaggedString *name, int n) {
+  FuncState *fs = ls->fs;
+  if (fs->nlocalvar+n < MAXLOCALS)
+    fs->localvar[fs->nlocalvar+n] = name;
+  else
+    luaX_error(ls, "too many local variables " MES_LIM(SMAXLOCALS));
+  luaI_registerlocalvar(fs, name, ls->linenumber);
+}
+
+
+static void add_localvar (LexState *ls, TaggedString *name) {
+  store_localvar(ls, name, 0);
+  ls->fs->nlocalvar++;
+}
+
+
+static int aux_localname (FuncState *fs, TaggedString *n) {
+  int i;
+  for (i=fs->nlocalvar-1; i >= 0; i--)
+    if (n == fs->localvar[i]) return i;  /* local var index */
+  return -1;  /* not found */
+}
+
+
+static void singlevar (LexState *ls, TaggedString *n, vardesc *var, int prev) {
+  FuncState *fs = prev ? ls->fs->prev : ls->fs;
+  int i = aux_localname(fs, n);
+  if (i >= 0) {  /* local value */
+    var->k = VLOCAL;
+    var->info = i;
+  }
+  else {  /* check shadowing */
+    FuncState *level = fs;
+    while ((level = level->prev) != NULL)
+      if (aux_localname(level, n) >= 0)
+        luaX_syntaxerror(ls, "cannot access a variable in outer scope", n->str);
+    var->k = VGLOBAL;
+    var->info = string_constant(fs, n);
+  }
+}
+
+
+static int indexupvalue (LexState *ls, TaggedString *n) {
+  FuncState *fs = ls->fs;
+  vardesc v;
+  int i;
+  singlevar(ls, n, &v, 1);
+  for (i=0; i<fs->nupvalues; i++) {
+    if (fs->upvalues[i].k == v.k && fs->upvalues[i].info == v.info)
+      return i;
+  }
+  /* new one */
+  if (++(fs->nupvalues) > MAXUPVALUES)
+    luaX_error(ls, "too many upvalues in a single function "
+                   MES_LIM(SMAXUPVALUES));
+  fs->upvalues[i] = v;  /* i = fs->nupvalues - 1 */
+  return i;
+}
+
+
+static void pushupvalue (LexState *ls, TaggedString *n) {
+  int i;
+  if (ls->fs->prev == NULL)
+    luaX_syntaxerror(ls, "cannot access upvalue in main", n->str);
+  if (aux_localname(ls->fs, n) >= 0)
+    luaX_syntaxerror(ls, "cannot access an upvalue in current scope", n->str);
+  i = indexupvalue(ls, n);
+  code_oparg(ls, PUSHUPVALUE, 2, i, 1);
+}
+
+
+
+static void check_debugline (LexState *ls) {
+  if (lua_debug && ls->linenumber != ls->fs->lastsetline) {
+    code_oparg(ls, SETLINE, 0, ls->linenumber, 0);
+    ls->fs->lastsetline = ls->linenumber;
+  }
+}
+
+
+static void adjuststack (LexState *ls, int n) {
+  if (n > 0)
+    code_oparg(ls, POP, 2, n-1, -n);
+  else if (n < 0)
+    code_oparg(ls, PUSHNIL, 1, (-n)-1, -n);
+}
+
+
+static void close_exp (LexState *ls, int pc, int nresults) {
+  if (pc > 0) {  /* expression is an open function call */
+    Byte *code = ls->fs->f->code;
+    int nparams = code[pc];  /* save nparams */
+    pc += fix_opcode(ls, pc-2, CALLFUNC, 2, nresults);
+    code[pc] = nparams;  /* restore nparams */
+    if (nresults != MULT_RET)
+      deltastack(ls, nresults);  /* "push" results */
+    deltastack(ls, -(nparams+1));  /* "pop" params and function */
+  }
+}
+
+
+static void adjust_mult_assign (LexState *ls, int nvars, listdesc *d) {
+  int diff = d->n - nvars;
+  if (d->pc == 0) {  /* list is closed */
+    /* push or pop eventual difference between list lengths */
+    adjuststack(ls, diff);
+  }
+  else {  /* must correct function call */
+    diff--;  /* do not count function call itself */
+    if (diff < 0) {  /* more variables than values */
+      /* function call must provide extra values */
+      close_exp(ls, d->pc, -diff);
+    }
+    else {  /* more values than variables */
+      close_exp(ls, d->pc, 0);  /* call should provide no value */
+      adjuststack(ls, diff);  /* pop eventual extra values */
+    }
+  }
+}
+
+
+static void code_args (LexState *ls, int nparams, int dots) {
+  FuncState *fs = ls->fs;
+  fs->nlocalvar += nparams;  /* "self" may already be there */
+  nparams = fs->nlocalvar;
+  if (!dots) {
+    fs->f->code[1] = nparams;  /* fill-in arg information */
+    deltastack(ls, nparams);
+  }
+  else {
+    fs->f->code[1] = nparams+ZEROVARARG;
+    deltastack(ls, nparams+1);
+    add_localvar(ls, luaS_new("arg"));
+  }
+}
+
+
+static void lua_pushvar (LexState *ls, vardesc *var) {
+  switch (var->k) {
+    case VLOCAL:
+      code_oparg(ls, PUSHLOCAL, 8, var->info, 1);
+      break;
+    case VGLOBAL:
+      code_oparg(ls, GETGLOBAL, 8, var->info, 1);
+      break;
+    case VDOT:
+      code_oparg(ls, GETDOTTED, 8, var->info, 0);
+      break;
+    case VINDEXED:
+      code_opcode(ls, GETTABLE, -1);
+      break;
+    case VEXP:
+      close_exp(ls, var->info, 1);  /* function must return 1 value */
+      break;
+  }
+  var->k = VEXP;
+  var->info = 0;  /* now this is a closed expression */
+}
+
+
+static void storevar (LexState *ls, vardesc *var) {
+  switch (var->k) {
+    case VLOCAL:
+      code_oparg(ls, SETLOCAL, 8, var->info, -1);
+      break;
+    case VGLOBAL:
+      code_oparg(ls, SETGLOBAL, 8, var->info, -1);
+      break;
+    case VINDEXED:
+      code_opcode(ls, SETTABLE0, -3);
+      break;
+    default:
+      LUA_INTERNALERROR("invalid var kind to store");
+  }
+}
+
+
+static int fix_jump (LexState *ls, int pc, OpCode op, int n) {
+  /* jump is relative to position following jump instruction */
+  return fix_opcode(ls, pc, op, 0, n-(pc+JMPSIZE));
+}
+
+
+static void fix_upjmp (LexState *ls, OpCode op, int pos) {
+  int delta = ls->fs->pc+JMPSIZE - pos;  /* jump is relative */
+  if (delta > 255) delta++;
+  code_oparg(ls, op, 0, delta, 0);
+}
+
+
+static void codeIf (LexState *ls, int thenAdd, int elseAdd) {
+  FuncState *fs = ls->fs;
+  int elseinit = elseAdd+JMPSIZE;
+  if (fs->pc == elseinit) {  /* no else part */
+    fs->pc -= JMPSIZE;
+    elseinit = fs->pc;
+  }
+  else
+    elseinit += fix_jump(ls, elseAdd, JMP, fs->pc);
+  fix_jump(ls, thenAdd, IFFJMP, elseinit);
+}
+
+
+static void func_onstack (LexState *ls, FuncState *func) {
+  FuncState *fs = ls->fs;
+  int i;
+  int c = next_constant(fs);
+  ttype(&fs->f->consts[c]) = LUA_T_PROTO;
+  fs->f->consts[c].value.tf = func->f;
+  if (func->nupvalues == 0)
+    code_constant(ls, c);
+  else {
+    for (i=0; i<func->nupvalues; i++)
+      lua_pushvar(ls, &func->upvalues[i]);
+    code_oparg(ls, CLOSURE, 0, c, -func->nupvalues+1);
+    code_byte(fs, func->nupvalues);
+  }
+}
+
+
+static void init_state (LexState *ls, FuncState *fs, TaggedString *filename) {
+  TProtoFunc *f = luaF_newproto();
+  fs->prev = ls->fs;  /* linked list of funcstates */
+  ls->fs = fs;
+  fs->stacksize = 0;
+  fs->maxstacksize = 0;
+  fs->nlocalvar = 0;
+  fs->nupvalues = 0;
+  fs->lastsetline = 0;
+  fs->f = f;
+  f->fileName = filename;
+  fs->pc = 0;
+  fs->maxcode = 0;
+  f->code = NULL;
+  fs->maxconsts = 0;
+  if (lua_debug)
+    fs->nvars = fs->maxvars = 0;
+  else
+    fs->maxvars = -1;  /* flag no debug information */
+  code_byte(fs, 0);  /* to be filled with stacksize */
+  code_byte(fs, 0);  /* to be filled with arg information */
+}
+
+
+static void close_func (LexState *ls) {
+  FuncState *fs = ls->fs;
+  TProtoFunc *f = fs->f;
+  code_opcode(ls, ENDCODE, 0);
+  f->code[0] = fs->maxstacksize;
+  f->code = luaM_reallocvector(f->code, fs->pc, Byte);
+  f->consts = luaM_reallocvector(f->consts, f->nconsts, TObject);
+  if (fs->maxvars != -1) {  /* debug information? */
+    luaI_registerlocalvar(fs, NULL, -1);  /* flag end of vector */
+    f->locvars = luaM_reallocvector(f->locvars, fs->nvars, LocVar);
+  }
+  ls->fs = fs->prev;
+}
+
+
+
+static int expfollow [] = {ELSE, ELSEIF, THEN, IF, WHILE, REPEAT, DO, NAME,
+   LOCAL, FUNCTION, END, UNTIL, RETURN, ')', ']', '}', ';', EOS, ',',  0};
+
+static int is_in (int tok, int *toks) {
+  int *t = toks;
+  while (*t) {
+    if (*t == tok)
+      return t-toks;
+    t++;
+  }
+  return -1;
+}
+
+
+static void next (LexState *ls) {
+  ls->token = luaX_lex(ls);
+}
+
+
+static void error_expected (LexState *ls, int token) {
+  char buff[100], t[TOKEN_LEN];
+  luaX_token2str(ls, token, t);
+  sprintf(buff, "`%s' expected", t);
+  luaX_error(ls, buff);
+}
+
+static void error_unmatched (LexState *ls, int what, int who, int where) {
+  if (where == ls->linenumber)
+    error_expected(ls, what);
+  else {
+    char buff[100];
+    char t_what[TOKEN_LEN], t_who[TOKEN_LEN];
+    luaX_token2str(ls, what, t_what);
+    luaX_token2str(ls, who, t_who);
+    sprintf(buff, "`%s' expected (to close `%s' at line %d)",
+            t_what, t_who, where);
+    luaX_error(ls, buff);
+  }
+}
+
+static void check (LexState *ls, int c) {
+  if (ls->token != c)
+    error_expected(ls, c);
+  next(ls);
+}
+
+static void check_match (LexState *ls, int what, int who, int where) {
+  if (ls->token != what)
+    error_unmatched(ls, what, who, where);
+  check_debugline(ls);  /* to 'mark' the 'what' */
+  next(ls);
+}
+
+static TaggedString *checkname (LexState *ls) {
+  TaggedString *ts;
+  if (ls->token != NAME)
+    luaX_error(ls, "`NAME' expected");
+  ts = ls->seminfo.ts;
+  next(ls);
+  return ts;
+}
+
+
+static int optional (LexState *ls, int c) {
+  if (ls->token == c) {
+    next(ls);
+    return 1;
+  }
+  else return 0;
+}
+
+
+TProtoFunc *luaY_parser (ZIO *z) {
+  struct LexState lexstate;
+  struct FuncState funcstate;
+  luaX_setinput(&lexstate, z);
+  init_state(&lexstate, &funcstate, luaS_new(zname(z)));
+  next(&lexstate);  /* read first token */
+  chunk(&lexstate);
+  if (lexstate.token != EOS)
+    luaX_error(&lexstate, "<eof> expected");
+  close_func(&lexstate);
+  return funcstate.f;
+}
+
+
+
+/*============================================================*/
+/* GRAMAR RULES */
+/*============================================================*/
+
+static void chunk (LexState *ls) {
+  /* chunk -> statlist ret */
+  statlist(ls);
+  ret(ls);
+}
+
+static void statlist (LexState *ls) {
+  /* statlist -> { stat [;] } */
+  while (stat(ls)) {
+    LUA_ASSERT(ls->fs->stacksize == ls->fs->nlocalvar,
+               "stack size != # local vars");
+    optional(ls, ';');
+  }
+}
+
+static int stat (LexState *ls) {
+  int line = ls->linenumber;  /* may be needed for error messages */
+  FuncState *fs = ls->fs;
+  switch (ls->token) {
+    case IF: {  /* stat -> IF ifpart END */
+      next(ls);
+      ifpart(ls);
+      check_match(ls, END, IF, line);
+      return 1;
+    }
+
+    case WHILE: {  /* stat -> WHILE cond DO block END */
+      TProtoFunc *f = fs->f;
+      int while_init = fs->pc;
+      int cond_end, cond_size;
+      next(ls);
+      cond_end = cond(ls);
+      check(ls, DO);
+      block(ls);
+      check_match(ls, END, WHILE, line);
+      cond_size = cond_end-while_init;
+      check_pc(fs, cond_size);
+      memcpy(f->code+fs->pc, f->code+while_init, cond_size);
+      luaO_memdown(f->code+while_init, f->code+cond_end, fs->pc-while_init);
+      while_init += JMPSIZE + fix_jump(ls, while_init, JMP, fs->pc-cond_size);
+      fix_upjmp(ls, IFTUPJMP, while_init);
+      return 1;
+    }
+
+    case DO: {  /* stat -> DO block END */
+      next(ls);
+      block(ls);
+      check_match(ls, END, DO, line);
+      return 1;
+    }
+
+    case REPEAT: {  /* stat -> REPEAT block UNTIL exp1 */
+      int repeat_init = fs->pc;
+      next(ls);
+      block(ls);
+      check_match(ls, UNTIL, REPEAT, line);
+      exp1(ls);
+      fix_upjmp(ls, IFFUPJMP, repeat_init);
+      deltastack(ls, -1);  /* pops condition */
+      return 1;
+    }
+
+    case FUNCTION: {  /* stat -> FUNCTION funcname body */
+      int needself;
+      vardesc v;
+      if (ls->fs->prev)  /* inside other function? */
+        return 0;
+      check_debugline(ls);
+      next(ls);
+      needself = funcname(ls, &v);
+      body(ls, needself, line);
+      storevar(ls, &v);
+      return 1;
+    }
+
+    case LOCAL: {  /* stat -> LOCAL localnamelist decinit */
+      listdesc d;
+      int nvars;
+      check_debugline(ls);
+      next(ls);
+      nvars = localnamelist(ls);
+      decinit(ls, &d);
+      ls->fs->nlocalvar += nvars;
+      adjust_mult_assign(ls, nvars, &d);
+      return 1;
+    }
+
+    case NAME: case '%': {  /* stat -> func | ['%'] NAME assignment */
+      vardesc v;
+      check_debugline(ls);
+      var_or_func(ls, &v);
+      if (v.k == VEXP) {  /* stat -> func */
+        if (v.info == 0)  /* is just an upper value? */
+          luaX_error(ls, "syntax error");
+        close_exp(ls, v.info, 0);
+      }
+      else {
+        int left = assignment(ls, &v, 1);  /* stat -> ['%'] NAME assignment */
+        adjuststack(ls, left);  /* remove eventual 'garbage' left on stack */
+      }
+      return 1;
+    }
+
+    case RETURN: case ';': case ELSE: case ELSEIF:
+    case END: case UNTIL: case EOS:  /* 'stat' follow */
+      return 0;
+
+    default:
+      luaX_error(ls, "<statement> expected");
+      return 0;  /* to avoid warnings */
+  }
+}
+
+static int SaveWord (LexState *ls) {
+  int res = ls->fs->pc;
+  check_pc(ls->fs, JMPSIZE);
+  ls->fs->pc += JMPSIZE;  /* open space */
+  return res;
+}
+
+static int SaveWordPop (LexState *ls) {
+  deltastack(ls, -1);  /* pop condition */
+  return SaveWord(ls);
+}
+
+static int cond (LexState *ls) {
+  /* cond -> exp1 */
+  exp1(ls);
+  return SaveWordPop(ls);
+}
+
+static void block (LexState *ls) {
+  /* block -> chunk */
+  FuncState *fs = ls->fs;
+  int nlocalvar = fs->nlocalvar;
+  chunk(ls);
+  adjuststack(ls, fs->nlocalvar - nlocalvar);
+  for (; fs->nlocalvar > nlocalvar; fs->nlocalvar--)
+    luaI_unregisterlocalvar(fs, ls->linenumber);
+}
+
+static int funcname (LexState *ls, vardesc *v) {
+  /* funcname -> NAME [':' NAME | '.' NAME] */
+  int needself = 0;
+  singlevar(ls, checkname(ls), v, 0);
+  if (ls->token == ':' || ls->token == '.') {
+    needself = (ls->token == ':');
+    next(ls);
+    lua_pushvar(ls, v);
+    code_string(ls, checkname(ls));
+    v->k = VINDEXED;
+  }
+  return needself;
+}
+
+static void body (LexState *ls, int needself, int line) {
+  /* body ->  '(' parlist ')' chunk END */
+  FuncState newfs;
+  init_state(ls, &newfs, ls->fs->f->fileName);
+  newfs.f->lineDefined = line;
+  check(ls, '(');
+  if (needself)
+    add_localvar(ls, luaS_new("self"));
+  parlist(ls);
+  check(ls, ')');
+  chunk(ls);
+  check_match(ls, END, FUNCTION, line);
+  close_func(ls);
+  func_onstack(ls, &newfs);
+}
+
+static void ifpart (LexState *ls) {
+  /* ifpart -> cond THEN block [ELSE block | ELSEIF ifpart] */
+  int c = cond(ls);
+  int e;
+  check(ls, THEN);
+  block(ls);
+  e = SaveWord(ls);
+  switch (ls->token) {
+    case ELSE:
+      next(ls);
+      block(ls);
+      break;
+
+    case ELSEIF:
+      next(ls);
+      ifpart(ls);
+      break;
+  }
+  codeIf(ls, c, e);
+}
+
+static void ret (LexState *ls) {
+  /* ret -> [RETURN explist sc] */
+  if (ls->token == RETURN) {
+    listdesc e;
+    check_debugline(ls);
+    next(ls);
+    explist(ls, &e);
+    close_exp(ls, e.pc, MULT_RET);
+    code_oparg(ls, RETCODE, 0, ls->fs->nlocalvar, 0);
+    ls->fs->stacksize = ls->fs->nlocalvar;  /* removes all temp values */
+    optional(ls, ';');
+  }
+}
+
+
+/*
+** For parsing expressions, we use a classic stack with priorities.
+** Each binary operator is represented by its index in "binop" + FIRSTBIN
+** (EQ=2, NE=3, ... '^'=13). The unary NOT is 0 and UNMINUS is 1.
+*/
+
+/* code of first binary operator */
+#define FIRSTBIN        2
+
+/* code for power operator (last operator)
+** '^' needs special treatment because it is right associative
+*/
+#define POW     13
+
+static int binop [] = {EQ, NE, '>', '<', LE, GE, CONC,
+                        '+', '-', '*', '/', '^', 0};
+
+static int priority [POW+1] =  {5, 5, 1, 1, 1, 1, 1, 1, 2, 3, 3, 4, 4, 6};
+
+static OpCode opcodes [POW+1] = {NOTOP, MINUSOP, EQOP, NEQOP, GTOP, LTOP,
+  LEOP, GEOP, CONCOP, ADDOP, SUBOP, MULTOP, DIVOP, POWOP};
+
+#define MAXOPS  20
+
+typedef struct {
+  int ops[MAXOPS];
+  int top;
+} stack_op;
+
+
+static void exp1 (LexState *ls) {
+  vardesc v;
+  exp(ls, &v);
+  lua_pushvar(ls, &v);
+  if (is_in(ls->token, expfollow) < 0)
+    luaX_error(ls, "ill formed expression");
+}
+
+
+static void exp (LexState *ls, vardesc *v) {
+  exp2(ls, v);
+  while (ls->token == AND || ls->token == OR) {
+    int is_and = (ls->token == AND);
+    int pc;
+    lua_pushvar(ls, v);
+    next(ls);
+    pc = SaveWordPop(ls);
+    exp2(ls, v);
+    lua_pushvar(ls, v);
+    fix_jump(ls, pc, (is_and?ONFJMP:ONTJMP), ls->fs->pc);
+  }
+}
+
+
+static void push (LexState *ls, stack_op *s, int op) {
+  if (s->top == MAXOPS)
+    luaX_error(ls, "expression too complex");
+  s->ops[s->top++] = op;
+}
+
+
+static void prefix (LexState *ls, stack_op *s) {
+  while (ls->token == NOT || ls->token == '-') {
+    push(ls, s, ls->token==NOT?0:1);
+    next(ls);
+  }
+}
+
+static void pop_to (LexState *ls, stack_op *s, int prio) {
+  int op;
+  while (s->top > 0 && priority[(op=s->ops[s->top-1])] >= prio) {
+    code_opcode(ls, opcodes[op], op<FIRSTBIN?0:-1);
+    s->top--;
+  }
+}
+
+static void exp2 (LexState *ls, vardesc *v) {
+  stack_op s;
+  int op;
+  s.top = 0;
+  prefix(ls, &s);
+  simpleexp(ls, v);
+  while ((op = is_in(ls->token, binop)) >= 0) {
+    op += FIRSTBIN;
+    lua_pushvar(ls, v);
+    /* '^' is right associative, so must 'simulate' a higher priority */
+    pop_to(ls, &s, (op == POW)?priority[op]+1:priority[op]);
+    push(ls, &s, op);
+    next(ls);
+    prefix(ls, &s);
+    simpleexp(ls, v);
+    lua_pushvar(ls, v);
+  }
+  if (s.top > 0) {
+    lua_pushvar(ls, v);
+    pop_to(ls, &s, 0);
+  }
+}
+
+
+static void simpleexp (LexState *ls, vardesc *v) {
+  check_debugline(ls);
+  switch (ls->token) {
+    case '(':  /* simpleexp -> '(' exp ')' */
+      next(ls);
+      exp(ls, v);
+      check(ls, ')');
+      break;
+
+    case NUMBER:  /* simpleexp -> NUMBER */
+      code_number(ls, ls->seminfo.r);
+      next(ls);
+      v->k = VEXP; v->info = 0;
+      break;
+
+    case STRING:  /* simpleexp -> STRING */
+      code_string(ls, ls->seminfo.ts);
+      next(ls);
+      v->k = VEXP; v->info = 0;
+      break;
+
+    case NIL:  /* simpleexp -> NIL */
+      adjuststack(ls, -1);
+      next(ls);
+      v->k = VEXP; v->info = 0;
+      break;
+
+    case '{':  /* simpleexp -> constructor */
+      constructor(ls);
+      v->k = VEXP; v->info = 0;
+      break;
+
+    case FUNCTION: {  /* simpleexp -> FUNCTION body */
+      int line = ls->linenumber;
+      next(ls);
+      body(ls, 0, line);
+      v->k = VEXP; v->info = 0;
+      break;
+    }
+
+    case NAME: case '%':
+      var_or_func(ls, v);
+      break;
+
+    default:
+      luaX_error(ls, "<expression> expected");
+      break;
+  }
+}
+
+static void var_or_func (LexState *ls, vardesc *v) {
+  /* var_or_func -> ['%'] NAME var_or_func_tail */
+  if (optional(ls, '%')) {  /* upvalue? */
+    pushupvalue(ls, checkname(ls));
+    v->k = VEXP;
+    v->info = 0;  /* closed expression */
+  }
+  else  /* variable name */
+    singlevar(ls, checkname(ls), v, 0);
+  var_or_func_tail(ls, v);
+}
+
+static void var_or_func_tail (LexState *ls, vardesc *v) {
+  for (;;) {
+    switch (ls->token) {
+      case '.':  /* var_or_func_tail -> '.' NAME */
+        next(ls);
+        lua_pushvar(ls, v);  /* 'v' must be on stack */
+        v->k = VDOT;
+        v->info = string_constant(ls->fs, checkname(ls));
+        break;
+
+      case '[':  /* var_or_func_tail -> '[' exp1 ']' */
+        next(ls);
+        lua_pushvar(ls, v);  /* 'v' must be on stack */
+        exp1(ls);
+        check(ls, ']');
+        v->k = VINDEXED;
+        break;
+
+      case ':':  /* var_or_func_tail -> ':' NAME funcparams */
+        next(ls);
+        lua_pushvar(ls, v);  /* 'v' must be on stack */
+        code_oparg(ls, PUSHSELF, 8, string_constant(ls->fs, checkname(ls)), 1);
+        v->k = VEXP;
+        v->info = funcparams(ls, 1);
+        break;
+
+      case '(': case STRING: case '{':  /* var_or_func_tail -> funcparams */
+        lua_pushvar(ls, v);  /* 'v' must be on stack */
+        v->k = VEXP;
+        v->info = funcparams(ls, 0);
+        break;
+
+      default: return;  /* should be follow... */
+    }
+  }
+}
+
+static int funcparams (LexState *ls, int slf) {
+  FuncState *fs = ls->fs;
+  int nparams = 1;  /* default value */
+  switch (ls->token) {
+    case '(': {  /* funcparams -> '(' explist ')' */
+      listdesc e;
+      next(ls);
+      explist(ls, &e);
+      check(ls, ')');
+      close_exp(ls, e.pc, 1);
+      nparams = e.n;
+      break;
+    }
+
+    case '{':  /* funcparams -> constructor */
+      constructor(ls);
+      break;
+
+    case STRING:  /* funcparams -> STRING */
+      next(ls);
+      break;
+
+    default:
+      luaX_error(ls, "function arguments expected");
+      break;
+  }
+  code_byte(fs, 0);  /* save space for opcode */
+  code_byte(fs, 0);  /* and nresult */
+  code_byte(fs, nparams+slf);
+  return fs->pc-1;
+}
+
+static void explist (LexState *ls, listdesc *d) {
+  switch (ls->token) {
+    case ELSE: case ELSEIF: case END: case UNTIL:
+    case EOS: case ';': case ')':
+      d->pc = 0;
+      d->n = 0;
+      break;
+
+    default:
+      explist1(ls, d);
+  }
+}
+
+static void explist1 (LexState *ls, listdesc *d) {
+  vardesc v;
+  exp(ls, &v);
+  d->n = 1;
+  while (ls->token == ',') {
+    d->n++;
+    lua_pushvar(ls, &v);
+    next(ls);
+    exp(ls, &v);
+  }
+  if (v.k == VEXP)
+    d->pc = v.info;
+  else {
+    lua_pushvar(ls, &v);
+    d->pc = 0;
+  }
+}
+
+static void parlist (LexState *ls) {
+  int nparams = 0;
+  int dots = 0;
+  switch (ls->token) {
+    case DOTS:  /* parlist -> DOTS */
+      next(ls);
+      dots = 1;
+      break;
+
+    case NAME:  /* parlist, tailparlist -> NAME [',' tailparlist] */
+      init:
+      store_localvar(ls, checkname(ls), nparams++);
+      if (ls->token == ',') {
+        next(ls);
+        switch (ls->token) {
+          case DOTS:  /* tailparlist -> DOTS */
+            next(ls);
+            dots = 1;
+            break;
+
+          case NAME:  /* tailparlist -> NAME [',' tailparlist] */
+            goto init;
+
+          default: luaX_error(ls, "NAME or `...' expected");
+        }
+      }
+      break;
+
+    case ')': break;  /* parlist -> empty */
+
+    default: luaX_error(ls, "NAME or `...' expected");
+  }
+  code_args(ls, nparams, dots);
+}
+
+static int localnamelist (LexState *ls) {
+  /* localnamelist -> NAME {',' NAME} */
+  int i = 1;
+  store_localvar(ls, checkname(ls), 0);
+  while (ls->token == ',') {
+    next(ls);
+    store_localvar(ls, checkname(ls), i++);
+  }
+  return i;
+}
+
+static void decinit (LexState *ls, listdesc *d) {
+  /* decinit -> ['=' explist1] */
+  if (ls->token == '=') {
+    next(ls);
+    explist1(ls, d);
+  }
+  else {
+    d->n = 0;
+    d->pc = 0;
+  }
+}
+
+static int assignment (LexState *ls, vardesc *v, int nvars) {
+  int left = 0;
+  /* dotted variables <a.x> must be stored like regular indexed vars <a["x"]> */
+  if (v->k == VDOT) {
+    code_constant(ls, v->info);
+    v->k = VINDEXED;
+  }
+  if (ls->token == ',') {  /* assignment -> ',' NAME assignment */
+    vardesc nv;
+    next(ls);
+    var_or_func(ls, &nv);
+    if (nv.k == VEXP)
+      luaX_error(ls, "syntax error");
+    left = assignment(ls, &nv, nvars+1);
+  }
+  else {  /* assignment -> '=' explist1 */
+    listdesc d;
+    check(ls, '=');
+    explist1(ls, &d);
+    adjust_mult_assign(ls, nvars, &d);
+  }
+  if (v->k != VINDEXED || left+(nvars-1) == 0) {
+    /* global/local var or indexed var without values in between */
+    storevar(ls, v);
+  }
+  else {  /* indexed var with values in between*/
+    code_oparg(ls, SETTABLE, 0, left+(nvars-1), -1);
+    left += 2;  /* table/index are not popped, because they aren't on top */
+  }
+  return left;
+}
+
+static void constructor (LexState *ls) {
+  /* constructor -> '{' part [';' part] '}' */
+  int line = ls->linenumber;
+  int pc = SaveWord(ls);
+  int nelems;
+  constdesc cd;
+  deltastack(ls, 1);
+  check(ls, '{');
+  part(ls, &cd);
+  nelems = cd.n;
+  if (ls->token == ';') {
+    constdesc other_cd;
+    next(ls);
+    part(ls, &other_cd);
+    if (cd.k == other_cd.k)  /* repeated parts? */
+      luaX_error(ls, "invalid constructor syntax");
+    nelems += other_cd.n;
+  }
+  check_match(ls, '}', '{', line);
+  fix_opcode(ls, pc, CREATEARRAY, 2, nelems);
+}
+
+static void part (LexState *ls, constdesc *cd) {
+  switch (ls->token) {
+    case ';': case '}':  /* part -> empty */
+      cd->n = 0;
+      cd->k = ls->token;
+      return;
+
+    case NAME: {
+      vardesc v;
+      exp(ls, &v);
+      if (ls->token == '=') {
+        switch (v.k) {
+          case VGLOBAL:
+            code_constant(ls, v.info);
+            break;
+          case VLOCAL:
+            code_string(ls, ls->fs->localvar[v.info]);
+            break;
+          default:
+            luaX_error(ls, "`=' unexpected");
+        }
+        next(ls);
+        exp1(ls);
+        cd->n = recfields(ls);
+        cd->k = 1;  /* record */
+      }
+      else {
+        lua_pushvar(ls, &v);
+        cd->n = listfields(ls);
+        cd->k = 0;  /* list */
+      }
+      break;
+    }
+
+    case '[':  /* part -> recfield recfields */
+      recfield(ls);
+      cd->n = recfields(ls);
+      cd->k = 1;  /* record */
+      break;
+
+    default:  /* part -> exp1 listfields */
+      exp1(ls);
+      cd->n = listfields(ls);
+      cd->k = 0;  /* list */
+      break;
+  }
+}
+
+static int recfields (LexState *ls) {
+  /* recfields -> { ',' recfield } [','] */
+  int n = 1;  /* one has been read before */
+  while (ls->token == ',') {
+    next(ls);
+    if (ls->token == ';' || ls->token == '}')
+      break;
+    recfield(ls);
+    n++;
+    if (n%RFIELDS_PER_FLUSH == 0)
+      flush_record(ls, RFIELDS_PER_FLUSH);
+  }
+  flush_record(ls, n%RFIELDS_PER_FLUSH);
+  return n;
+}
+
+static int listfields (LexState *ls) {
+  /* listfields -> { ',' exp1 } [','] */
+  int n = 1;  /* one has been read before */
+  while (ls->token == ',') {
+    next(ls);
+    if (ls->token == ';' || ls->token == '}')
+      break;
+    exp1(ls);
+    n++;
+    if (n%LFIELDS_PER_FLUSH == 0)
+      flush_list(ls, n/LFIELDS_PER_FLUSH - 1, LFIELDS_PER_FLUSH);
+  }
+  flush_list(ls, n/LFIELDS_PER_FLUSH, n%LFIELDS_PER_FLUSH);
+  return n;
+}
+
+static void recfield (LexState *ls) {
+  /* recfield -> (NAME | '['exp1']') = exp1 */
+  switch (ls->token) {
+    case NAME:
+      code_string(ls, checkname(ls));
+      break;
+
+    case '[':
+      next(ls);
+      exp1(ls);
+      check(ls, ']');
+      break;
+
+    default: luaX_error(ls, "NAME or `[' expected");
+  }
+  check(ls, '=');
+  exp1(ls);
+}
+