executable semantics/syntax: move to a subpackage.

2026-10-05 22:02:55 +01:00 · 2021-03-04 18:45:54 -08:00
parent 18690b43bb
commit 45c487de70
7 changed files with 70 additions and 60 deletions
@@ -0,0 +1,95 @@
+/*
+Part of the Carbon Language project, under the Apache License v2.0 with LLVM
+Exceptions. See /LICENSE for license information.
+SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+*/
+
+%{
+#include <cstdlib>
+#include "executable_semantics/syntax/syntax.tab.h"
+%}
+
+/* Turn off legacy bits we don't need */
+%option noyywrap nounput nodefault noinput
+
+/* maintains the number of the current line read from input in the
+   global variable yylineno.
+*/
+%option yylineno
+
+AND      "and"
+ARROW    "->"
+AUTO     "auto"
+BOOL     "Bool"
+BREAK    "break"
+CASE     "case"
+CHOICE   "choice"
+COMMENT  \/\/[^\n]*\n
+CONTINUE "continue"
+DBLARROW "=>"
+DEFAULT  "default"
+ELSE     "else"
+EQUAL    "=="
+FALSE    "false"
+FN       "fn"
+FNTY     "fnty"
+IF       "if"
+INT      "Int"
+MATCH    "match"
+NOT      "not"
+OR       "or"
+RETURN   "return"
+STRUCT   "struct"
+TRUE     "true"
+TYPE     "Type"
+VAR      "var"
+WHILE    "while"
+
+identifier    [A-Za-z_][A-Za-z0-9_]*
+integer_literal   [0-9]+
+
+%%
+
+{AND}      { return AND; }
+{ARROW}    { return ARROW; }
+{AUTO}     { return AUTO; }
+{BOOL}     { return BOOL; }
+{BREAK}    { return BREAK; }
+{CASE}     { return CASE; }
+{CHOICE}   { return CHOICE; }
+{COMMENT}  ;
+{CONTINUE} { return CONTINUE; }
+{DBLARROW} { return DBLARROW; }
+{DEFAULT}  { return DEFAULT; }
+{ELSE}     { return ELSE; }
+{EQUAL}    { return EQUAL; }
+{FALSE}    { return FALSE; }
+{FN}       { return FN; }
+{FNTY}     { return FNTY; }
+{IF}       { return IF; }
+{INT}      { return INT; }
+{MATCH}    { return MATCH; }
+{NOT}      { return NOT; }
+{OR}       { return OR; }
+{RETURN}   { return RETURN; }
+{STRUCT}   { return STRUCT; }
+{TRUE}     { return TRUE; }
+{TYPE}     { return TYPE; }
+{VAR}      { return VAR; }
+{WHILE}    { return WHILE; }
+
+{identifier} {
+  int n = strlen(yytext);
+  yylval.str = reinterpret_cast<char*>(malloc((n + 1) * sizeof(char)));
+  strncpy(yylval.str, yytext, n + 1);
+  return identifier;
+}
+{integer_literal} {
+  yylval.num = atof(yytext);
+  return integer_literal;
+}
+
+[ \t\n]+ ;
+. { return yytext[0]; }
+
+%%