diff --git a/Cargo.toml b/Cargo.toml
index 89037b1..bf185dc 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "hexo"
-version = "0.9.1"
+version = "0.9.2"
 edition = "2021"
 license = "Apache-2.0"
 repository = "https://github.com/lexa-diky/hexo"
diff --git a/grammar.pest b/grammar.pest
index 1feed8d..50b2609 100644
--- a/grammar.pest
+++ b/grammar.pest
@@ -1,18 +1,27 @@
+// default symbols
 WHITESPACE = _{ " "+ }
 COMMENT = _{ "//" ~ (!"\n" ~ ANY)+ }
 
+// language custom symbols
+GL_EMIT = _{ ">" }
+GL_CONST = _{ "$" }
+GL_FN = _{ "#" }
+SY_BRO = _{ "(" }
+SY_BRC = _{ ")" }
+SY_UNDERSCORE = _{ "_" }
+
 // IDENTIFIER
-identifier = _{ (ASCII_ALPHANUMERIC | "_")+ }
+identifier = _{ (ASCII_ALPHANUMERIC | SY_UNDERSCORE)+ }
 
 
 file = _{ SOI ~ body ~ EOI }
-body = _{ "\n"* ~ (statement ~ "\n"+) * ~ statement? }
+body = _{ NEWLINE* ~ (statement ~ NEWLINE+) * ~ statement? }
 
 statement = _{ const_statement | emit_statement | fn_statement }
-	emit_statement = { ">" ~ atomic_strip }
-    const_statement = { "$" ~ const_statement_name ~ atomic_strip }
+	emit_statement = { GL_EMIT ~ atomic_strip }
+    const_statement = { GL_CONST ~ const_statement_name ~ atomic_strip }
         const_statement_name = @{ identifier }
-    fn_statement = { "#" ~ fn_statement_name ~ fn_statement_body }
+    fn_statement = { GL_FN ~ fn_statement_name ~ fn_statement_body }
         fn_statement_name = @{ identifier }
         fn_statement_body = { "{" ~ body ~ "}" }
 
@@ -27,9 +36,9 @@ atom = _{ atom_body ~ WHITESPACE? }
     atom_utf8 = { ( "''" | (!"'" ~ ANY) )* }
    		atom_utf8_decor = _{ "'" ~ atom_utf8 ~ "'" }
     atom_const = @{ identifier }
-		atom_const_decor = _{ "$" ~ atom_const }
+		atom_const_decor = _{ GL_CONST ~ atom_const }
 
-	atom_fn = { "#" ~ atom_fn_name ~ "(" ~ atom_fn_params? ~ ")" }
+	atom_fn = { GL_FN ~ atom_fn_name ~ SY_BRO ~ atom_fn_params? ~ SY_BRC }
     	atom_fn_name = { identifier }
         atom_fn_params = { (atom_fn_param ~ ",")* ~ atom_fn_param }
         atom_fn_param_identifier = { identifier }
diff --git a/sample.hexo b/sample.hexo
index 8ce030a..c6087ad 100644
--- a/sample.hexo
+++ b/sample.hexo
@@ -1 +1,2 @@
-> #eval(#read_file('samples/java_object/input.hexo'))
\ No newline at end of file
+> #eval(#read_file('samples/java_object/input.hex'))
+
diff --git a/src/compiler/rst/compiler.rs b/src/compiler/rst/compiler.rs
index 0633ae9..ba23cb8 100644
--- a/src/compiler/rst/compiler.rs
+++ b/src/compiler/rst/compiler.rs
@@ -88,8 +88,7 @@ impl RstCompiler<'_> {
 
             for param in params {
                 let mut param_buffer = ByteBuffer::default();
-                self.build_bytes_into(context_id, context, param.value(), &mut param_buffer)
-                    .unwrap();
+                self.build_bytes_into(context_id, context, param.value(), &mut param_buffer)?;
 
                 params_buffer.insert(param.name().to_string(), param_buffer);
             }
diff --git a/src/util/logger.rs b/src/util/logger.rs
index b1d0212..314e4c6 100644
--- a/src/util/logger.rs
+++ b/src/util/logger.rs
@@ -49,7 +49,7 @@ impl HexoLogger {
     }
 
     pub(crate) fn error(&self, message: &str) {
-        eprintln!("{message}");
+        eprintln!("{}", style(message).red());
     }
 
     pub(crate) fn info(&self, message: &str) {