diff --git a/src/parser/grammar.c b/src/parser/grammar.c
index 6a192db..33551f5 100644
--- a/src/parser/grammar.c
+++ b/src/parser/grammar.c
@@ -66,7 +66,7 @@ static bool init_firsts_map(void)
     firsts_map = calloc(NUMBER_OF_RULES, sizeof(struct firsts_list));
     if (firsts_map == NULL)
     {
-        puts("Internal error: couldn't create the firsts_map (is your memory "
+        perror("Internal error: couldn't create the firsts_map (is your memory "
              "full ?)");
         return false;
     }
@@ -161,7 +161,7 @@ struct firsts_list *first(enum rule rule)
 {
     if (firsts_map == NULL || firsts_map[rule].tokens == NULL)
     {
-        puts("Internal error: attempted to get the firsts of a rule without "
+        perror("Internal error: attempted to get the firsts of a rule without "
              "properly initializing the firsts map");
         return NULL;
     }
@@ -208,7 +208,7 @@ struct ast *parse_input(struct lexer_context *ctx)
         return ast;
     }
 
-    puts("Syntax error: expected newline or EOF after list");
+    perror("Syntax error: expected newline or EOF after list");
     ast_free(&ast);
     return NULL;
 }
diff --git a/src/parser/grammar_advanced.c b/src/parser/grammar_advanced.c
index aac5742..9416eba 100644
--- a/src/parser/grammar_advanced.c
+++ b/src/parser/grammar_advanced.c
@@ -6,6 +6,8 @@
 
 #include "grammar_basic.h"
 
+bool
+
 struct ast *parse_redirection(struct lexer_context *ctx)
 {
     struct token *token = PEEK_TOKEN();
@@ -17,20 +19,20 @@ struct ast *parse_redirection(struct lexer_context *ctx)
         token = PEEK_TOKEN();
     }
 
-    if (token->type != TOKEN_REDIRECTION)
+    if (!is_token_redir(token))
     {
-        puts("Syntax error: expected a redirection token but got something "
+        perror("Syntax error: expected a redirection token but got something "
              "else");
         return NULL;
     }
-    char *redir_op = strdup(token->data);
+    // char *redir_op = strdup(token->data);
     POP_TOKEN();
 
     token = PEEK_TOKEN();
     if (token->type != TOKEN_WORD)
     {
-        puts("Syntax error: expected a word after redirection");
-        free(redir_op);
+        perror("Syntax error: expected a word after redirection");
+        // free(redir_op);
         return NULL;
     }
     char *target = strdup(token->data);
diff --git a/src/parser/grammar_basic.c b/src/parser/grammar_basic.c
index 0b3b7c6..d229549 100644
--- a/src/parser/grammar_basic.c
+++ b/src/parser/grammar_basic.c
@@ -160,7 +160,7 @@ struct ast *parse_command(struct lexer_context *ctx)
     }
     else
     {
-        puts("Syntax error: unexpected token");
+        perror("Syntax error: unexpected token");
         return NULL;
     }
 }
@@ -173,7 +173,7 @@ struct ast *parse_simple_command(struct lexer_context *ctx)
     struct token *token = POP_TOKEN();
     if (token->type != TOKEN_WORD)
     {
-        puts("Expected a command but got a different token type");
+        perror("Expected a command but got a different token type");
         return NULL;
     }
     char *command = strdup(token->data);
@@ -202,12 +202,12 @@ struct ast *parse_simple_command(struct lexer_context *ctx)
         else if (ast_is_redir(element))
         {
             // TODO
-            puts("NOT IMPLEMENTED");
+            perror("NOT IMPLEMENTED");
             return NULL;
         }
         else
         {
-            puts("Internal error: unexpected return value from parse_element "
+            perror("Internal error: unexpected return value from parse_element "
                  "in parse_simple_command");
             list_deep_destroy(command_elements);
             return NULL;
@@ -241,7 +241,7 @@ struct ast *parse_element(struct lexer_context *ctx)
     }
     else
     {
-        puts("Syntax error: unexpected token at parse_element");
+        perror("Syntax error: unexpected token at parse_element");
         return NULL;
     }
 }
@@ -257,7 +257,7 @@ struct ast *parse_if_rule(struct lexer_context *ctx)
     struct token *token = POP_TOKEN();
     if (token->type != TOKEN_IF)
     {
-        puts("Internal error: expected a if rule but token has different "
+        perror("Internal error: expected a if rule but token has different "
              "type");
         return NULL;
     }
@@ -270,7 +270,7 @@ struct ast *parse_if_rule(struct lexer_context *ctx)
     if (token->type != TOKEN_THEN)
     {
         ast_free(&condition_content);
-        puts("Expected the 'then' keyword but token has different type");
+        perror("Expected the 'then' keyword but token has different type");
         return NULL;
     }
 
@@ -299,7 +299,7 @@ struct ast *parse_if_rule(struct lexer_context *ctx)
         ast_free(&condition_content);
         ast_free(&then_content);
         ast_free(&else_content);
-        puts("Expected the 'fi' keyword but token has different type");
+        perror("Expected the 'fi' keyword but token has different type");
         return NULL;
     }
 
@@ -311,7 +311,7 @@ struct ast *parse_if_rule(struct lexer_context *ctx)
         ast_free(&condition_content);
         ast_free(&then_content);
         ast_free(&else_content);
-        puts("Internal error: could not create a new AST (AST_IF)");
+        perror("Internal error: could not create a new AST (AST_IF)");
         return NULL;
     }
 
@@ -396,7 +396,7 @@ struct ast *parse_else_clause(struct lexer_context *ctx)
         token = POP_TOKEN();
         if (token->type != TOKEN_THEN)
         {
-            puts("Expected the 'then' keyword but got a different token type");
+            perror("Expected the 'then' keyword but got a different token type");
             return NULL;
         }
 
diff --git a/src/parser/parser.c b/src/parser/parser.c
index b86c696..b71867a 100644
--- a/src/parser/parser.c
+++ b/src/parser/parser.c
@@ -14,7 +14,7 @@ bool parser_init(void)
 {
     if (state == PARSER_STATE_READY)
     {
-        puts("Internal error: tried to initialize the parser module twice.");
+        perror("Internal error: tried to initialize the parser module twice.");
         return NULL;
     }
     int success = grammar_init();
@@ -29,19 +29,19 @@ struct ast *get_ast(struct lexer_context *ctx)
 {
     if (ctx == NULL)
     {
-        puts("Internal error: called parser with no lexer context (NULL "
+        perror("Internal error: called parser with no lexer context (NULL "
              "pointer). Aborting.");
         return NULL;
     }
     if (state == PARSER_STATE_NOT_INITIALIZED)
     {
-        puts("Internal error: attempted to call parser without initializing "
+        perror("Internal error: attempted to call parser without initializing "
              "it. Aborting.");
         return NULL;
     }
     if (state == PARSER_STATE_CLOSED)
     {
-        puts("Internal error: attempted to call parser after closing it. "
+        perror("Internal error: attempted to call parser after closing it. "
              "Aborting.");
         return NULL;
     }
diff --git a/src/utils/ast/ast.c b/src/utils/ast/ast.c
index a507a33..a099473 100644
--- a/src/utils/ast/ast.c
+++ b/src/utils/ast/ast.c
@@ -11,7 +11,7 @@ void ast_free(struct ast **node)
 {
     if (node == NULL || *node == NULL)
     {
-        puts(
+        perror(
             "WARNING: Internal error: failed to free AST node (NULL argument)");
         return;
     }
@@ -45,7 +45,7 @@ void ast_free(struct ast **node)
         break;
 
     default:
-        puts("WARNING: Internal error: failed to free an AST node (Unknown "
+        perror("WARNING: Internal error: failed to free an AST node (Unknown "
              "type)");
         return;
     }