add_variable_declaration

Makefile

@@ -1,4 +1,4 @@
 comp:
 	lex src/lex.l
 	yacc -d src/grammar.y
-	gcc -o bin/main y.tab.c lex.yy.c src/summoner.c src/interpreter.c
+	gcc -o bin/main y.tab.c lex.yy.c src/create.c src/interpreter.c src/compiler.c main/main.c

main/main.c

@@ -0,0 +1,22 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include "../src/summoner.h"
+
+int main(int argc, char *argv[])
+{
+    Compiler *compiler = malloc(sizeof(Compiler));
+    set_current_compiler(compiler);
+
+    extern int yyparse();
+    extern FILE *yyin;
+    yyin = fopen(argv[1], "r");
+    if (yyin == NULL)
+    {
+        printf("fail to open file:%s\n", argv[1]);
+    }
+    else
+    {
+        yyparse();
+    }
+    return 0;
+}

src/compiler.c

@@ -0,0 +1,13 @@
+#include "summoner.h"
+
+static Compiler *st_current_compiler;
+
+Compiler *get_current_compiler()
+{
+    return st_current_compiler;
+}
+
+void set_current_compiler(Compiler *compiler)
+{
+    st_current_compiler = compiler;
+}

src/create.c

@@ -81,6 +81,14 @@ Statement *alloc_if_statement(Expression *condition, Block *then_block, Elseif *
     return stmt;
 }
 
+Statement *alloc_declaration_stmt(char *name, TypeSpecifier *type, Expression *initializer)
+{
+    Statement *stmt = alloc_statement(DECLARATION_STATEMENT);
+    Declaration *decl_s = malloc(sizeof(Declaration));
+    stmt->u.decl_s = decl_s;
+    return stmt;
+}
+
 Statement *alloc_block_statement(Block *block)
 {
     Statement *stmt = alloc_statement(BLOCK_STATEMENT);
@@ -133,9 +141,35 @@ Elseif *chain_else_if_list(Elseif *list, Elseif *elseif)
     return list;
 }
 
+Block *open_block()
+{
+    Block *new_block;
+    Compiler *compiler = get_current_compiler();
+    new_block = alloc_block(NULL);
+    new_block->outer_block = compiler->current_block;
+    compiler->current_block = new_block;
+    return new_block;
+}
+
+Block *close_block(Block *block, StatementList *stmt_list)
+{
+    Compiler *compiler = get_current_compiler();
+    block->statement_list = stmt_list;
+    compiler->current_block = block->outer_block;
+    return block;
+}
+
 Block *alloc_block(StatementList *list)
 {
     Block *block = malloc(sizeof(Block));
-    block->statemen_list = list;
+    block->statement_list = list;
     return block;
 }
+
+TypeSpecifier *alloc_type_specifier(BasicType type, char *identifier)
+{
+    TypeSpecifier *type_s = malloc(sizeof(TypeSpecifier));
+    type_s->basic_type = type;
+    type_s->identifier = identifier;
+    return type_s;
+}

src/grammar.y

@@ -1,7 +1,6 @@
 %{
 #include <stdio.h>
 #include <stdlib.h>
-#include "src/ast.h"
 #include "src/summoner.h"
 #include "src/interpreter.h"
 
@@ -18,21 +17,24 @@ int yyerror(const char *s);
     struct StatementList *statement_list;
     struct Block *block;
     struct Elseif *elseif;
+    struct TypeSpecifier *type_specifier;
 }
 
 %token <int_value> BOOL_LITERAL
 %token <double_value> DOUBLE_LITERAL
 %token <int_value> INT_LITERAL
 %token <identifier> IDENTIFIER;
-%token FUNCTION IF ELSE FOR RETURN BREAK CONTINUE NIL
+%token VAR FUNCTION IF ELSE FOR RETURN BREAK CONTINUE NIL
+%token BOOL_T INT_T DOUBLE_T STRING_T
 
 %type <expression> expr bool_expr
-%type <statement> stmt if_stmt
+%type <statement> stmt if_stmt declaration_stmt
 %type <statement_list> stmt_list
 %type <block> block
 %type <elseif> elseif elseif_list
+%type <type_specifier> type_specifier
 
-%nonassoc '='
+%nonassoc '=' DECL_ASSIGN
 %left AND OR
 %nonassoc EQ NE
 %nonassoc '>' '<' LE GE
@@ -53,8 +55,23 @@ stmt:
      | IDENTIFIER '=' expr { $$ = alloc_assign_statement($1, $3); }
      | block               { $$ = alloc_block_statement($1); }
      | if_stmt
+     | declaration_stmt
      ;
 
+declaration_stmt:
+                    VAR IDENTIFIER type_specifier          { $$ = alloc_declaration_stmt($2, $3, NULL); }
+                  | VAR IDENTIFIER type_specifier '=' expr { $$ = alloc_declaration_stmt($2, $3, $5); }
+                  | VAR IDENTIFIER '=' expr                { $$ = alloc_declaration_stmt($2, NULL, $4); }
+                  | IDENTIFIER DECL_ASSIGN expr            { $$ = alloc_declaration_stmt($1, NULL, $3); }
+                  ;
+
+type_specifier:
+                BOOL_T   { $$ = alloc_type_specifier(BOOLEAN_TYPE, NULL); }
+              | INT_T    { $$ = alloc_type_specifier(INT_TYPE, NULL); }
+              | DOUBLE_T { $$ = alloc_type_specifier(DOUBLE_TYPE, NULL); }
+              | STRING_T { $$ = alloc_type_specifier(STRING_T, NULL); }
+              ;
+
 if_stmt:
           IF bool_expr block                        { $$ = alloc_if_statement($2, $3, NULL, NULL); }
         | IF bool_expr block ELSE block             { $$ = alloc_if_statement($2, $3, NULL, $5); } 
@@ -72,11 +89,15 @@ elseif:
        ;
 
 block:
-         '{' stmt_list '}'                     { $$ = alloc_block($2); }
-       | '{' new_line stmt_list '}'            { $$ = alloc_block($3); }
-       | '{' stmt_list new_line '}'            { $$ = alloc_block($2); }
-       | '{' new_line stmt_list new_line '}'   { $$ = alloc_block($3); }
-       | '{' new_line '}'                      { $$ = alloc_block(NULL); }
+         '{' stmt_list                         { $<block>$ = open_block(); }
+                       '}'                     { $$ = close_block($<block>3, $2); }
+       | '{' new_line stmt_list                { $<block>$ = open_block(); }
+                                '}'            { $$ = close_block($<block>4, $3); }
+       | '{' stmt_list new_line                { $<block>$ = open_block(); }
+                                '}'            { $$ = close_block($<block>4, $2); }
+       | '{' new_line stmt_list new_line       { $<block>$ = open_block(); }
+                                         '}'   { $$ = close_block($<block>5, $3); }
+       | '{' new_line '}'                      { $<block>$ = alloc_block(NULL); }
        | '{' '}'                               { $$ = alloc_block(NULL); }
      ;
 
@@ -117,16 +138,3 @@ int yyerror(char const *str) {
     fprintf(stderr, "parse error near %s\n", yytext);
     return 0;
 }
-
-int main(int argc, char *argv[]) {
-    extern FILE *yyin;
-    yyin = fopen(argv[1], "r");
-    if(yyin==NULL)
-    {
-        printf("fail to open file:%s\n", argv[1]);
-    } else 
-    {
-        yyparse();
-    }
-    return 0;
-}

src/lex.l

@@ -10,6 +10,7 @@
     return *yytext;
 }
 
+":="       return DECL_ASSIGN;
 ">="       return GE;
 "<="       return LE;
 "=="       return EQ;
@@ -20,10 +21,15 @@
 "else"     return ELSE;
 "for"      return FOR;
 "nil"      return NIL;
+"var"      return VAR;
 "func"     return FUNCTION;
 "return"   return RETURN;
 "break"    return BREAK;
 "continue" return CONTINUE;
+"bool"     return BOOL_T;
+"int"      return INT_T;
+"double"   return DOUBLE_T;
+"string"   return STRING_T;
 
 "true"|"false" {
     yylval.int_value = strcmp(yytext, "false");

src/summoner.h

@@ -45,8 +45,25 @@ typedef enum
     NOT_EXPRESSION, /* ! */
 } ExpressionKind;
 
+typedef enum
+{
+    INTERFACE_TYPE = 1,
+    BOOLEAN_TYPE,
+    INT_TYPE,
+    DOUBLE_TYPE,
+    STRING_TYPE,
+    STRUCT_TYPE,
+} BasicType;
+
+typedef struct TypeSpecifier
+{
+    BasicType basic_type;
+    char *identifier;
+} TypeSpecifier;
+
 typedef struct Expression
 {
+    TypeSpecifier *type;
     ExpressionKind kind;
     union
     {
@@ -83,8 +100,16 @@ typedef enum
     RETURN_STATEMENT,
     BREAK_STATEMENT,
     CONTINUE_STATEMENT,
+    DECLARATION_STATEMENT,
 } StatementKind;
 
+typedef struct Declaration
+{
+    char *name;
+    TypeSpecifier *type;
+    Expression *initializer;
+} Declaration;
+
 typedef struct AssignStatement
 {
     char *variable;
@@ -96,7 +121,8 @@ typedef struct Statement
     StatementKind kind;
     union
     {
-        AssignStatement *assign_s;
+        struct AssignStatement *assign_s;
+        struct Declaration *decl_s;
         struct Block *block_s;
         struct IfStatement *if_s;
     } u;
@@ -110,7 +136,8 @@ typedef struct StatementList
 
 typedef struct Block
 {
-    StatementList *statemen_list;
+    StatementList *statement_list;
+    struct Block *outer_block;
 } Block;
 
 typedef struct Elseif
@@ -132,10 +159,23 @@ Statement *alloc_statement(StatementKind kind);
 Statement *alloc_assign_statement(char *variable, Expression *operand);
 Statement *alloc_block_statement(Block *block);
 Statement *alloc_if_statement(Expression *condition, Block *then_block, Elseif *elseif_list, Block *else_block);
+Statement *alloc_declaration_stmt(char *name, TypeSpecifier *type, Expression *initializer);
 StatementList *alloc_statement_list(Statement *statement);
 StatementList *chain_statement_list(StatementList *list, Statement *statement);
 Elseif *alloc_else_if(Expression *condition, Block *block);
 Elseif *chain_else_if_list(Elseif *list, Elseif *elseif);
+Block *open_block();
+Block *close_block(Block *block, StatementList *stmt_list);
 Block *alloc_block(StatementList *list);
 
+TypeSpecifier *alloc_type_specifier(BasicType type, char *identifier);
+
+typedef struct Compiler
+{
+    Block *current_block;
+} Compiler;
+
+Compiler *get_current_compiler();
+void set_current_compiler(Compiler *compiler);
+
 #endif