'Minor' bug fix for the StatementList, forgot to set the capacity.

Makefile

@@ -1,5 +1,5 @@
 CC = gcc
-CFLAGS=-g -Wall -DDEBUG
+CFLAGS=-g -Wall -DDEBUG -Wpedantic
 SRCDIR=src
 OBJDIR=obj
 SRCS=$(wildcard $(SRCDIR)/*.c)
@@ -11,7 +11,7 @@ BIN=$(BINDIR)/clox
 
 all: $(BIN)
 
-release: CFLAGS=-Wall -O2
+release: CFLAGS=-Wall -Wpedantic -O2
 release: clean
 release: $(BIN)
 

src/lox.c

@@ -13,6 +13,10 @@ void RunPrompt(void);
 char* GetFileContents(const char*);
 
 int main(int argc, char** argv) {
+    #ifdef DEBUG
+        printf("Debug clox build.\n");
+    #endif
+    
     if (argc > 2) {
         printf("Useage: clox [script]\n");
         exit(EX_USAGE);
@@ -39,13 +43,16 @@ void RunFile(const char* path) {
     char* contents = GetFileContents(path);
     TokenList* tokens = ScanTokens(contents);
     free(contents);
-    Print(tokens);
-    printf("TREE:\n");
-    Expr* tree = GenerateExpressionTree(tokens);
-    PrintExpressionTree(tree);
+    printf("TOKENS:\n");
+    //Print(tokens);
+    printf("EXPRESSION TREE:\n");
+    //Expr* tree = GenerateExpressionTree(tokens);
+    StatementList* statements = Parse(tokens);
+    //PrintExpressionTree(tree);
     printf("\n");
-    Interpret(tree);
-    FreeExpressionTree(tree);
+    //Interpret(tree);
+    FreeStatementList(statements);
+    //FreeExpressionTree(tree);
     DestroyTokenList(tokens);
 }
 

src/parser.c

@@ -1,7 +1,10 @@
 #include "parser.h"
 #include "expr.h"
+#include "statement.h"
 #include "token.h"
 #include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 
 Expr* Expression(void);
 Expr* Equality(void);
@@ -10,6 +13,11 @@ Expr* Term(void);
 Expr* Factor(void);
 Expr* Unary(void);
 Expr* Primary(void);
+Stmt* Statement(void);
+Stmt* PrintStatement(void);
+Stmt* ExpressionStatement(void);
+StatementList* CreateStatementList(void);
+int AddStatementToList(Stmt*, StatementList*);
 int Match(int, ...);
 int Check(TokenType);
 int ParserAtEnd(void);
@@ -17,14 +25,29 @@ Token* ParserPeek(void);
 Token* Previous(void);
 Token* AdvanceParser(void);
 void SynchronizeParser(void);
+void FreeExpressionTree(Expr*);
 
 const TokenList* ListOfTokens;
 int Current = 0;
 
-Expr* GenerateExpressionTree(const TokenList* list) {
+StatementList* Parse(const TokenList* list) {
     ListOfTokens = list;
+    StatementList* statements = CreateStatementList();
+    Stmt* statement = NULL;
 
-    return Expression();
+    if (!statements) return NULL;
+
+    while(!ParserAtEnd()) {
+        statement = Statement();
+        if (!statement) { 
+            fprintf(stderr, "[Warn] No statement generated\n");
+            continue;
+        }
+
+        AddStatementToList(statement, statements);
+    }
+
+    return statements;
 }
 
 //Simply expands the equality rule
@@ -32,6 +55,40 @@ Expr* Expression() {
     return Equality();
 }
 
+Stmt* Statement(void) {
+    if (Match(1, PRINT)) return PrintStatement();
+
+    return ExpressionStatement();
+}
+
+Stmt* PrintStatement(void) {
+    Expr* value = Expression();
+
+    if (!Match(1, Semicolon)) { 
+        fprintf(stderr, "Expected ';' after value\n");
+        return NULL;
+    }
+
+    AdvanceParser();
+
+    return CreateStatement(value, STMT_Print);
+}
+
+Stmt* ExpressionStatement(void) {
+    Expr* expr = Expression();
+
+    if (!Match(1, Semicolon)) { 
+        fprintf(stderr, "Expected ';' after expression\n");
+        return NULL;
+    }
+
+    AdvanceParser();
+
+    return CreateStatement(expr, STMT_Expression);
+}
+
+Stmt* ExpressionStatement(void);
+
 Expr* Equality() {
     Expr* expr = Comparison();
 
@@ -146,7 +203,7 @@ Expr* Primary() {
         return temp;
     }
 
-    printf("Bad expression\n");
+    fprintf(stderr, "Bad expression, this should be unreachable.\n");
 
     return NULL;
 }
@@ -253,4 +310,57 @@ void FreeExpressionTree(Expr* tree) {
     }
 
     free(tree);
+}
+
+void FreeStatementList(StatementList* list) {
+    if (!list) return;
+
+    for(int i = 0; i < list->size; i++) {
+        FreeExpressionTree(list->content[i]->expression);
+        free(list->content[i]);
+    }
+
+    free(list);
+}
+
+StatementList* CreateStatementList(void) {
+    StatementList* list = calloc(1, sizeof(StatementList));
+
+    if (!list) {
+        fprintf(stderr, "Failed to calloc StatementList. %s\n", strerror(errno));
+        return NULL;
+    }
+
+    list->content = calloc(STATEMENTLIST_DEFAULT_SIZE, sizeof(Stmt));
+
+    if (!list->content) {
+        fprintf(stderr, "Failed to calloc StatementList contents. %s\n", strerror(errno));
+        free(list);
+        return NULL;
+    }
+
+    list->capacity = STATEMENTLIST_DEFAULT_SIZE;
+
+    return list;
+}
+
+int AddStatementToList(Stmt* statement, StatementList* list) {
+    if (!statement || !list) return 0;
+
+    if (list->size == list->capacity) {
+        void* new_ptr = realloc(list->content, sizeof(Stmt) * list->capacity * 2);
+
+        if (!new_ptr) {
+            fprintf(stderr, "Failed to realloc StatmentList to size %d. %s\n", list->capacity * 2, strerror(errno));
+            return 0;
+        }
+
+        list->content = new_ptr;
+        list->capacity *= 2;
+    }
+
+    list->content[list->size] = statement;
+    list->size++;
+
+    return 1;
 }

src/parser.h

@@ -4,12 +4,21 @@
 #include "expr.h"
 #include "scanner.h"
 #include "token.h"
+#include "statement.h"
 #include <stdarg.h>
 #include <stdlib.h>
 #include <string.h>
 
-Expr* GenerateExpressionTree(const TokenList* list);
+#define STATEMENTLIST_DEFAULT_SIZE 32
+
+typedef struct {
+    Stmt** content;
+    int size;
+    int capacity;
+} StatementList;
+
+StatementList* Parse(const TokenList*);
 void PrintExpressionTree(const Expr*);
-void FreeExpressionTree(Expr*);
+void FreeStatementList(StatementList*);
 
 #endif

src/statement.c

@@ -0,0 +1,21 @@
+#include "statement.h"
+
+Stmt* CreateStatement(Expr* expression, StatementType type) {
+    Stmt* stmt = calloc(1, sizeof(Stmt));
+
+    if (!stmt) {
+        fprintf(stderr, "Failed to calloc space for Statement. %s.\n", strerror(errno));
+        return NULL;
+    }
+
+    stmt->expression = expression;
+    stmt->type = type;
+
+    return stmt;
+}
+
+void FreeStatement(Stmt* stmt) {
+    if (!stmt) return;
+    
+    free(stmt);
+}

src/statement.h

@@ -0,0 +1,22 @@
+#ifndef STATEMENT_H
+#define STATEMENT_H
+
+#include "expr.h"
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+typedef enum {
+    STMT_Expression,
+    STMT_Print
+} StatementType;
+
+typedef struct stmt {
+    StatementType type;
+    Expr* expression;
+} Stmt;
+
+Stmt* CreateStatement(Expr*, StatementType);
+void FreeStatement(Stmt*);
+
+#endif