Second parser version before deadline

README.md

@@ -1,18 +1,18 @@
-# CPPython
+# CPPython - Lexer/Parser
 
 ## Requirements
 
 - Flex 2.6.4
+- Bison 3.5.1
 - GCC 9.3.0
+- Make 4.2.1
 
 ## Usage
 
 ```bash
-$ cd src
-$ chmod +x build.sh
-$ ./build.sh
-$ ./cppython tests/valid_1.ppy  # for valid test
-$ ./cppython tests/incorrect_1.ppy  # for invalid test
+$ make
+$ ./cppython tests/parser/valid_1.ppy  # for valid test
+$ ./cppython tests/parser/invalid_1.ppy  # for invalid test
 ```
 
 ## Author

src/Makefile

@@ -1,15 +1,15 @@
-FILES	= parser.c lexer.c ast.c sym_tab.c main.c 
+FILES	= parser/parser.c lexer/lexer.c core/ast.c core/sym_tab.c core/main.c 
 CFLAGS	= -g -Wall -pedantic -x c
 CC		= gcc
 
-cppython:	$(FILES) ast.h sym_tab.h
-			$(CC) $(CFLAGS) $(FILES) -o cppython -lfl
+cppython:	$(FILES) core/ast.h core/sym_tab.h
+			$(CC) $(CFLAGS) $(FILES) -I core -I lexer -I parser -o cppython -lfl
 
-lexer.c:	cppython.lex
-			flex cppython.lex
+lexer/lexer.c:	lexer/cppython.lex
+				flex lexer/cppython.lex
 
-parser.c:	cppython.y
-			bison -d -v cppython.y
+parser/parser.c:	parser/cppython.y
+					bison -d -v parser/cppython.y
 
 clean:
-	rm -f *.o *~ lexer.c lexer.h parser.c parser.h parser.output cppython
+	rm -f *.o *~ lexer/lexer.c lexer/lexer.h parser/parser.c parser/parser.h parser/parser.output cppython

src/README.md

@@ -1,20 +1,6 @@
-# CPPython - Lexer
+# CPPython - Lexer/Parser
 
-## Requirements
-
-- Flex 2.6.4
-- Bison 3.5.1
-- GCC 9.3.0
-
-## Usage
-
-```bash
-$ make
-$ ./cppython tests/parser/valid_1.ppy  # for valid test
-$ ./cppython tests/parser/invalid_1.ppy  # for invalid test
-```
-
-## Output examples
+## Examples
 
 - Valid input 1:
   - Commands: ./cppython tests/parser/valid_1.ppy
@@ -58,8 +44,3 @@ $ ./cppython tests/parser/invalid_1.ppy  # for invalid test
 
 		LexerError: line 1, column 2, token '^' is not recognized
     ```
-
-## Author
-
-Name: Dayanne Fernandes da Cunha  
-University ID: 130107191

src/core/ast.c

@@ -0,0 +1,75 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include "ast.h"
+
+ast_node* create_bin_expr(char *operator, ast_node* left, ast_node* right) {
+    if (PARSER_VERBOSE) printf("\nCreating binary expression node: .%d. .%s. .%d.\n",
+                               left->op.integer_expr, operator, right->op.integer_expr);
+    ast_node* expr = (ast_node*) malloc(sizeof(ast_node));
+    expr->tag = BINARY_TYPE;
+    expr->op.binary_expr.operator = operator;
+    expr->op.binary_expr.left = left;
+    expr->op.binary_expr.right = right;
+    return expr;
+}
+
+ast_node* create_int_expr(int value) {
+    if (PARSER_VERBOSE) printf("\n\nCreating integer expression node: %d\n", value);
+    ast_node* expr = (ast_node*) malloc(sizeof(ast_node));
+    expr->tag = INTEGER_TYPE;
+    expr->op.integer_expr = value;
+    return expr;
+}
+
+void create_ast(ast_node* expression) {
+    if (PARSER_VERBOSE) printf("\nCreating AST.\n");
+    root = expression;
+    return;
+}
+
+void create_empy_ast() {
+    if (PARSER_VERBOSE) printf("\nCreating empty AST.\n");
+    root = NULL;
+    return;
+}
+
+ast_node* print_exp(ast_node* node) {
+    if (PARSER_VERBOSE) {
+        if (node == NULL) {
+            printf("Empty expression.\n");
+        } else {
+            printf("TAG: %d\n", node->tag);
+        }
+    }
+    return node;
+}
+
+void print_ast(ast_node* node) {
+    if (node == NULL) {
+        printf("Empty AST.\n");
+        return;
+    }
+
+    if (PARSER_VERBOSE) printf("TAG: %d\n", node->tag);
+
+    for (int i=0; i < AST_LVL; ++i) printf("  ");
+
+    // terminal leaf
+    if (node->tag == INTEGER_TYPE) {
+        printf("INT: %d\n", node->op.integer_expr);
+        return;
+    // terminal leaf
+    } else if (node->tag == VAR_TYPE) {
+        printf("VAR: %s\n", node->op.variable_expr);
+        return;
+    // non terminal node
+    } else if (node->tag == BINARY_TYPE) {
+        printf("OP: %s\n", node->op.binary_expr.operator);
+        AST_LVL += 1;
+        print_ast(node->op.binary_expr.right);
+        print_ast(node->op.binary_expr.left);
+    } else {
+        printf("Print AST unknown error.\n");
+        return;
+    }
+}

src/ast.h → src/core/ast.h

@@ -1,28 +1,35 @@
 #ifndef __AST_H__
 #define __AST_H__
 
+int LEX_VERBOSE, PARSER_VERBOSE, MAIN_VERBOSE, AST_LVL;
 int line, column;
 
+enum TAG {
+    INTEGER_TYPE=0, 
+    VAR_TYPE, 
+    BINARY_TYPE
+};
+
 typedef struct exp {
+    int tag;
     union { 
         int integer_expr;
-        char *string_expr;
         char *variable_expr;
         struct { 
             char *operator;
             struct exp* left;
             struct exp* right;
         } binary_expr;
-      } op;
+    } op;
 } ast_node;
 
-typedef struct expr_list { 
-    ast_node* head;
-    struct expr_list* next;
-} ast;
+ast_node* root;
+
+void print_ast(ast_node* node);
+ast_node* print_exp(ast_node* node);
 
+void create_empy_ast();
 void create_ast(ast_node* expression);
-ast_node* show(ast_node* expression);
 ast_node* create_int_expr(int value);
 ast_node* create_bin_expr(char *operator, ast_node* left, ast_node* right);
 

src/main.c → src/core/main.c

@@ -5,18 +5,22 @@
 
 int main (int argc, char *argv[]) {
 	printf("Welcome to CPPython interpreter:\n");
+    MAIN_VERBOSE = LEX_VERBOSE = PARSER_VERBOSE = AST_LVL = 0;
+    root = NULL;
 
     // init lexer and parser
     printf("Lexer/parser:\n");
     line = column = 1;
     yyin = fopen(argv[1], "r");
-    printf("\nline %d. ", line);
+    if (MAIN_VERBOSE) printf("\nline %d. ", line);
     do {
         yyparse();
     } while (!feof(yyin));
     fclose(yyin);
-    printf("\n");
-    printf("Lexer and parser finished.\n\n");
+    printf("\nLexer and parser finished.\n\n");
+
+    printf("Abstract Syntax Tree:\n");
+    print_ast(root);
 
     return 0;
 }

src/cppython.lex → src/lexer/cppython.lex

@@ -6,7 +6,7 @@
 	#include "ast.h"
 	#include "parser.h"
 
-	enum TOKENS{
+	enum TOKENS {
 		ERROR_TOK=1,
 		NEWLINE_TOK,
 		WHITESPACE_TOK,
@@ -26,7 +26,7 @@
 	};
 %}
 
-%option outfile="lexer.c" header-file="lexer.h"
+%option outfile="lexer/lexer.c" header-file="lexer/lexer.h"
 %option nounput
 %option noinput
 
@@ -96,33 +96,33 @@ NUMBER			({INTEGER}|{FLOAT})
 void handle_token(int token) {
 	switch (token) {
 		case INTEGER_TOK:
-			printf("Token: <integer, '%s'>", yytext);
+			if (LEX_VERBOSE) printf("Token: <integer, '%s'>", yytext);
 			yylval.value = atoi(yytext); 
 			break;
 		case SUB_TOK:
-			printf("Token: <sub, '%s'>", yytext);
+			if (LEX_VERBOSE) printf("Token: <sub, '%s'>", yytext);
 			yylval.op = yytext;
 			break;
 		case ADD_TOK:
-			printf("Token: <add, '%s'>", yytext);
+			if (LEX_VERBOSE) printf("Token: <add, '%s'>", yytext);
 			yylval.op = yytext;
 			break;
 		case MULT_TOK:
-			printf("Token: <mult, '%s'>", yytext);
+			if (LEX_VERBOSE) printf("Token: <mult, '%s'>", yytext);
 			yylval.op = yytext;
 			break;
 		case DIV_TOK:
-			printf("Token: <div, '%s'>", yytext);
+			if (LEX_VERBOSE) printf("Token: <div, '%s'>", yytext);
 			yylval.op = yytext;
 			break;
 		case NEWLINE_TOK:
 			line += 1;
 			column = 0;  // reset column index 
-			printf("\nline %d. ", line);
+			if (LEX_VERBOSE) printf("\nline %d. ", line);
 			break;
 		case ERROR_TOK:
-			printf("\nLexerError: line %d, column %d, token '%s' is not recognized\n",
-				   line, column, yytext);
+			if (LEX_VERBOSE) printf("\nLexerError: line %d, column %d, token '%s' is not recognized\n",
+				   				line, column, yytext);
 			exit(1);
 		default:
 			break;  // ignore