Merge pull request #238 from PlutoLang/use

Add pluto_use
PlutoLang · Apr 12, 2023 · 1d395bb · 1d395bb
2 parents 3980f5f + 075d141
commit 1d395bb
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Showing 4 changed files with 136 additions and 87 deletions.
diff --git a/src/llex.cpp b/src/llex.cpp
@@ -46,31 +46,9 @@ static const char *const luaX_tokens [] = {
     "end", "false", "for", "function", "goto", "if",
     "in", "local", "nil", "not", "or", "repeat",
     "case", "default", "as", "begin", "extends", "instanceof",
-#ifdef PLUTO_COMPATIBLE_CLASS
-    "class",
-#endif
+    "pluto_use",
     "pluto_switch", "pluto_continue", "pluto_enum", "pluto_new", "pluto_class", "pluto_parent", "pluto_export",
-#ifndef PLUTO_COMPATIBLE_SWITCH
-    "switch",
-#endif
-#ifndef PLUTO_COMPATIBLE_CONTINUE
-    "continue",
-#endif
-#ifndef PLUTO_COMPATIBLE_ENUM
-    "enum",
-#endif
-#ifndef PLUTO_COMPATIBLE_NEW
-    "new",
-#endif
-#ifndef PLUTO_COMPATIBLE_CLASS
-    "class",
-#endif
-#ifndef PLUTO_COMPATIBLE_PARENT
-    "parent",
-#endif
-#ifndef PLUTO_COMPATIBLE_EXPORT
-    "export",
-#endif
+          "switch",       "continue",       "enum",       "new",       "class",       "parent",       "export",
     "pluto_suggest_0", "pluto_suggest_1",
     "return", "then", "true", "until", "while",
     "//", "..", "...", "==", ">=", "<=", "~=",

diff --git a/src/llex.h b/src/llex.h
@@ -39,32 +39,9 @@ enum RESERVED {
   TK_DO, TK_ELSE, TK_ELSEIF, TK_END, TK_FALSE, TK_FOR, TK_FUNCTION,
   TK_GOTO, TK_IF, TK_IN, TK_LOCAL, TK_NIL, TK_NOT, TK_OR, TK_REPEAT,
   TK_CASE, TK_DEFAULT, TK_AS, TK_BEGIN, TK_EXTENDS, TK_INSTANCEOF, // New narrow keywords.
-#ifdef PLUTO_COMPATIBLE_CLASS
-  TK_CLASS,
-#endif
-  TK_PSWITCH, TK_PCONTINUE, TK_PENUM, TK_PNEW, TK_PCLASS, TK_PPARENT, TK_PEXPORT, // New compatibility keywords.
-  /* New non-compatible keywords. */
-#ifndef PLUTO_COMPATIBLE_SWITCH
-  TK_SWITCH,
-#endif
-#ifndef PLUTO_COMPATIBLE_CONTINUE
-  TK_CONTINUE,
-#endif
-#ifndef PLUTO_COMPATIBLE_ENUM
-  TK_ENUM,
-#endif
-#ifndef PLUTO_COMPATIBLE_NEW
-  TK_NEW,
-#endif
-#ifndef PLUTO_COMPATIBLE_CLASS
-  TK_CLASS,
-#endif
-#ifndef PLUTO_COMPATIBLE_PARENT
-  TK_PARENT,
-#endif
-#ifndef PLUTO_COMPATIBLE_EXPORT
-  TK_EXPORT,
-#endif
+  TK_PUSE, // New compatibility keywords.
+  TK_PSWITCH, TK_PCONTINUE, TK_PENUM, TK_PNEW, TK_PCLASS, TK_PPARENT, TK_PEXPORT,
+  TK_SWITCH, TK_CONTINUE, TK_ENUM, TK_NEW, TK_CLASS, TK_PARENT, TK_EXPORT, // New non-compatible keywords.
   TK_SUGGEST_0, TK_SUGGEST_1, // New special keywords.
   TK_RETURN, TK_THEN, TK_TRUE, TK_UNTIL, TK_WHILE,
   /* other terminal symbols */
@@ -87,6 +64,9 @@ enum RESERVED {
   TK_WALRUS,            /* walrus operator */
 };
 
+#define FIRST_COMPAT TK_PUSE
+#define FIRST_NON_COMPAT TK_PSWITCH
+#define FIRST_SPECIAL TK_SUGGEST_0
 #define LAST_RESERVED TK_WHILE
 
 /* number of reserved words */
@@ -159,12 +139,24 @@ struct Token {
   [[nodiscard]] bool IsNarrow() const noexcept
   {
     return token == TK_IN
-      || (token >= TK_CASE && token < TK_PSWITCH)
-#ifdef PLUTO_COMPATIBLE_CLASS
-      || token == TK_CLASS
-#endif
+      || (token >= TK_CASE && token < FIRST_COMPAT)
       ;
   }
+
+  [[nodiscard]] bool IsCompatible() const noexcept
+  {
+      return (token >= FIRST_COMPAT && token < FIRST_NON_COMPAT);
+  }
+
+  [[nodiscard]] bool IsNonCompatible() const noexcept
+  {
+      return (token >= FIRST_NON_COMPAT && token < FIRST_SPECIAL);
+  }
+
+  [[nodiscard]] bool IsSpecial() const noexcept
+  {
+	  return (token >= FIRST_SPECIAL && token < TK_RETURN);
+  }
 };
 
 

diff --git a/src/lparser.cpp b/src/lparser.cpp
@@ -1500,11 +1500,7 @@ static void classexpr (LexState *ls, expdesc *t) {
     field(ls, &cc);
     (testnext(ls, ',') || testnext(ls, ';'));
   }
-#ifdef PLUTO_COMPATIBLE_CLASS
-  check_match(ls, TK_END, TK_PCLASS, line);
-#else
   check_match(ls, TK_END, TK_CLASS, line);
-#endif
   lastlistfield(fs, &cc);
   luaK_settablesize(fs, pc, t->u.info, cc.na, cc.nh);
 }
@@ -2390,9 +2386,7 @@ static void primaryexp (LexState *ls, expdesc *v) {
       }
       return;
     }
-#ifndef PLUTO_COMPATIBLE_PARENT
     case TK_PARENT:
-#endif
     case TK_PPARENT: {
       luaX_next(ls);
       parentexp(ls, v);
@@ -2599,17 +2593,13 @@ static void simpleexp (LexState *ls, expdesc *v, int flags, TypeDesc *prop) {
       lambdabody(ls, v, ls->getLineNumber());
       return;
     }
-#ifndef PLUTO_COMPATIBLE_NEW
     case TK_NEW:
-#endif
     case TK_PNEW: {
       if (prop) *prop = VT_TABLE;
       newexpr(ls, v);
       return;
     }
-#ifndef PLUTO_COMPATIBLE_CLASS
     case TK_CLASS:
-#endif
     case TK_PCLASS: {
       if (prop) *prop = VT_TABLE;
       luaX_next(ls); /* skip 'class' */
@@ -3258,7 +3248,9 @@ static void enumstat (LexState *ls) {
   EnumDesc *ed = nullptr;
   bool is_enum_class = false;
   if (gett(ls) != TK_BEGIN) { /* enum has name (and possibly modifier)? */
-    if (gett(ls) == TK_CLASS) {
+    if (ls->t.token == TK_CLASS
+      || (ls->t.token == TK_NAME && strcmp(ls->t.seminfo.ts->contents, "class") == 0)
+      ) {
       is_enum_class = true;
       luaX_next(ls);
     }
@@ -3918,6 +3910,76 @@ static void retstat (LexState *ls, TypeDesc *prop) {
 }
 
 
+static int checkkeyword (LexState *ls) {
+  if (ls->t.token == TK_NAME)
+    for (int i = FIRST_NON_COMPAT; i != FIRST_SPECIAL; ++i)
+      if (strcmp(luaX_reserved2str(i), ls->t.seminfo.ts->contents) == 0) {
+        luaX_next(ls);
+        return i;
+      }
+  if (!ls->t.IsNonCompatible()) {
+    if (ls->t.IsCompatible())
+      luaX_syntaxerror(ls, "expected non-compatible keyword");
+    luaX_syntaxerror(ls, "expected keyword");
+  }
+  int token = ls->t.token;
+  luaX_next(ls);
+  return token;
+}
+
+static void disablekeyword (LexState *ls, int token) {
+  auto i = ls->tokens.begin();
+  if (ls->tidx != -1)
+    i += ls->tidx;  /* don't apply retroactively */
+  for (; i != ls->tokens.end(); ++i)
+    if (i->token == token)
+      i->token = TK_NAME;
+}
+
+
+static void enablekeyword (LexState *ls, int token) {
+  const char* str = luaX_reserved2str(token);
+  auto i = ls->tokens.begin() + ls->tidx;
+  TString* ts = nullptr;
+  /* find first instance of token */
+  for (; i != ls->tokens.end(); ++i)
+    if (i->token == TK_NAME && strcmp(str, i->seminfo.ts->contents) == 0) {
+      ts = i->seminfo.ts;
+      i->token = token;
+      break;
+    }
+  /* find further instances of the token; faster now that we have TString */
+  if (ts)
+    for (; i != ls->tokens.end(); ++i)
+      if (i->token == TK_NAME && eqstr(i->seminfo.ts, ts))
+        i->token = token;
+}
+
+static void usestat (LexState *ls) {
+  luaX_next(ls); /* skip 'pluto_use' */
+  do {
+    bool is_enabled = (ls->t.token != TK_NAME);
+    int token = checkkeyword(ls);
+    bool enable = true;
+    if (testnext(ls, '=')) {
+      if (testnext(ls, TK_FALSE))
+        enable = false;
+      else checknext(ls, TK_FALSE);
+    }
+    if (is_enabled != enable) {
+      if (enable)
+        enablekeyword(ls, token);
+      else
+        disablekeyword(ls, token);
+    }
+  } while (testnext(ls, ','));
+
+  /* update ls->t */
+  luaX_prev(ls);
+  luaX_next(ls);
+}
+
+
 static void statement (LexState *ls, TypeDesc *prop) {
   if (ls->shouldSuggest()) {
     SuggestionsState ss(ls);
@@ -3986,9 +4048,7 @@ static void statement (LexState *ls, TypeDesc *prop) {
       funcstat(ls, line);
       break;
     }
-#ifndef PLUTO_COMPATIBLE_CLASS
     case TK_CLASS:
-#endif
     case TK_PCLASS: {
       classstat(ls);
       break;
@@ -4004,19 +4064,13 @@ static void statement (LexState *ls, TypeDesc *prop) {
       }
       if (testnext(ls, TK_FUNCTION))  /* local function? */
         localfunc(ls);
-#ifdef PLUTO_COMPATIBLE_CLASS
-      else if (testnext(ls, TK_PCLASS))
-#else
-      else if (testnext(ls, TK_CLASS) || testnext(ls, TK_PCLASS))
-#endif
+      else if (testnext2(ls, TK_CLASS, TK_PCLASS))
         localclass(ls);
       else
         localstat(ls);
       break;
     }
-#ifndef PLUTO_COMPATIBLE_EXPORT
     case TK_EXPORT:
-#endif
     case TK_PEXPORT: {
       if (ls->fs->bl->previous)
         luaX_syntaxerror(ls, "Attempt to use 'export' outside of global scope");
@@ -4033,11 +4087,7 @@ static void statement (LexState *ls, TypeDesc *prop) {
         luaX_prev(ls);
         localfunc(ls);
       }
-#ifdef PLUTO_COMPATIBLE_CLASS
-      else if (testnext(ls, TK_PCLASS)) {
-#else
-      else if (testnext(ls, TK_CLASS) || testnext(ls, TK_PCLASS)) {
-#endif
+      else if (testnext2(ls, TK_CLASS, TK_PCLASS)) {
         ls->export_symbols.emplace_back(str_checkname(ls, true));
         luaX_prev(ls);
         localclass(ls);
@@ -4063,9 +4113,7 @@ static void statement (LexState *ls, TypeDesc *prop) {
       breakstat(ls);
       break;
     }
-#ifndef PLUTO_COMPATIBLE_CONTINUE
     case TK_CONTINUE:
-#endif
     case TK_PCONTINUE: {
       continuestat(ls);
       break;
@@ -4075,20 +4123,20 @@ static void statement (LexState *ls, TypeDesc *prop) {
       gotostat(ls);
       break;
     }
-#ifndef PLUTO_COMPATIBLE_SWITCH
     case TK_SWITCH:
-#endif
     case TK_PSWITCH: {
       switchstat(ls, line);
       break;
     }
-#ifndef PLUTO_COMPATIBLE_ENUM
     case TK_ENUM:
-#endif
     case TK_PENUM: {
       enumstat(ls);
       break;
     }
+    case TK_PUSE: {
+      usestat(ls);
+      break;
+    }
     default: {  /* stat -> func | assignment */
       exprstat(ls);
       break;
@@ -4111,9 +4159,7 @@ static void builtinoperators (LexState *ls) {
   /* discover what operators are used */
   for (const auto& t : ls->tokens) {
     switch (t.token) {
-#ifndef PLUTO_COMPATIBLE_NEW
       case TK_NEW:
-#endif
       case TK_PNEW:
         uses_new = true;
         break;
@@ -4371,6 +4417,27 @@ LClosure *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff,
   lexstate.dyd = dyd;
   dyd->actvar.n = dyd->gt.n = dyd->label.n = 0;
   luaX_setinput(L, &lexstate, z, funcstate.f->source, firstchar);
+#ifdef PLUTO_COMPATIBLE_SWITCH
+  disablekeyword(&lexstate, TK_SWITCH);
+#endif
+#ifdef PLUTO_COMPATIBLE_CONTINUE
+  disablekeyword(&lexstate, TK_CONTINUE);
+#endif
+#ifdef PLUTO_COMPATIBLE_ENUM
+  disablekeyword(&lexstate, TK_ENUM);
+#endif
+#ifdef PLUTO_COMPATIBLE_NEW
+  disablekeyword(&lexstate, TK_NEW);
+#endif
+#ifdef PLUTO_COMPATIBLE_CLASS
+  disablekeyword(&lexstate, TK_CLASS);
+#endif
+#ifdef PLUTO_COMPATIBLE_PARENT
+  disablekeyword(&lexstate, TK_PARENT);
+#endif
+#ifdef PLUTO_COMPATIBLE_EXPORT
+  disablekeyword(&lexstate, TK_EXPORT);
+#endif
   mainfunc(&lexstate, &funcstate);
   lua_assert(!funcstate.prev && funcstate.nups == 1 && !lexstate.fs);
   /* all scopes should be correctly finished */

diff --git a/tests/basic.pluto b/tests/basic.pluto
@@ -1033,6 +1033,18 @@ do
     assert(c == 3)
 end
 
+print "Testing pluto_use."
+do
+    pluto_use class = false
+
+    local class = { class = "class" }
+    assert(class.class == "class")
+
+    pluto_use class
+
+    class Human end
+end
+
 print "Testing compatibility."
 do
     local a = "Hi"