tristan/fddl
1
0
Fork 0
mirror of https://github.com/urinalcaketopper/fddl.git synced 2025-06-07 05:34:47 +00:00
Code Issues Packages Projects Releases Wiki Activity

if/while parsing

Browse Source
This commit is contained in:
Tristan 2025-05-17 18:49:23 -04:00
parent 9dbbf7741e
commit 9f594e3775
2 changed files with 43 additions and 34 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
src/main.rs
View File

@ -71,7 +71,7 @@ fn run(source: String) {
loop { loop {
if parser.is_at_end() { // Add is_at_end to Parser if not already public if parser.is_at_end() {
break; break;
} }

75
src/parser/parser.rs
View File

@ -351,17 +351,20 @@ impl Parser {
Some(Statement::Block(statements)) Some(Statement::Block(statements))
} }
fn parse_if_statement(&mut self) -> Option<Statement> { fn parse_if_statement(&mut self) -> Option<Statement> {
if !self.match_token(Token::If) { return None; } if !self.match_token(Token::If) {
eprintln!("Internal parser error: Expected 'if' token in parse_if_statement.");
return None;
}
if !self.match_token(Token::LeftParen) { if !self.match_token(Token::LeftParen) {
eprintln!("Error: Expected '(' after 'if'."); eprintln!("Error: Expected '(' after 'if'.");
return None; return None;
} }
let condition = self.parse_expression()?; let condition = self.parse_expression()?;
if !self.match_token(Token::RightParen) { if !self.match_token(Token::RightParen) {
eprintln!("Error: Expected ')' after if condition."); eprintln!("Error: Expected ')' after if condition.");
return None; return None;
} }
if !self.check(&Token::LeftBrace) { if !self.check(&Token::LeftBrace) {
@ -370,30 +373,36 @@ impl Parser {
} }
let then_branch = Box::new(self.parse_statement()?); let then_branch = Box::new(self.parse_statement()?);
let mut else_branch = None; let mut else_branch_opt: Option<Box<Statement>> = None;
if self.match_token(Token::Else) { if self.match_token(Token::Else) {
if !self.check(&Token::LeftBrace) && !self.check(&Token::If) { if self.check(&Token::LeftBrace) {
eprintln!("Error: Expected '{{' for else statement body or 'if' for 'else if'."); else_branch_opt = Some(Box::new(self.parse_statement()?));
} else if self.check(&Token::If) {
else_branch_opt = Some(Box::new(self.parse_statement()?));
} else {
eprintln!("Error: Expected '{{' or 'if' after 'else'.");
return None; return None;
} }
else_branch = Some(Box::new(self.parse_statement()?));
} }
Some(Statement::IfStatement(condition, then_branch, else_branch)) Some(Statement::IfStatement(condition, then_branch, else_branch_opt))
} }
fn parse_while_statement(&mut self) -> Option<Statement> { fn parse_while_statement(&mut self) -> Option<Statement> {
if !self.match_token(Token::While) { return None; } if !self.match_token(Token::While) {
eprintln!("Internal parser error: Expected 'while' token in parse_while_statement.");
return None;
}
if !self.match_token(Token::LeftParen) { if !self.match_token(Token::LeftParen) {
eprintln!("Error: Expected '(' after 'while'."); eprintln!("Error: Expected '(' after 'while'.");
return None; return None;
} }
let condition = self.parse_expression()?; let condition = self.parse_expression()?;
if !self.match_token(Token::RightParen) { if !self.match_token(Token::RightParen) {
eprintln!("Error: Expected ')' after while condition."); eprintln!("Error: Expected ')' after while condition.");
return None; return None;
} }
if !self.check(&Token::LeftBrace) { if !self.check(&Token::LeftBrace) {
eprintln!("Error: Expected '{{' for while statement body."); eprintln!("Error: Expected '{{' for while statement body.");
@ -402,22 +411,22 @@ impl Parser {
let body = Box::new(self.parse_statement()?); let body = Box::new(self.parse_statement()?);
Some(Statement::WhileStatement(condition, body)) Some(Statement::WhileStatement(condition, body))
} }
fn parse_print_statement(&mut self) -> Option<Statement> { fn parse_print_statement(&mut self) -> Option<Statement> {
if !self.match_token(Token::Print) { return None; } if !self.match_token(Token::Print) { return None; }
let value = self.parse_expression()?; let value = self.parse_expression()?;
if self.match_token(Token::Semicolon) { if !self.match_token(Token::Semicolon) {
Some(Statement::PrintStatement(value))
} else {
eprintln!("Error: Expected ';' after print value."); eprintln!("Error: Expected ';' after print value.");
None None
} else {
Some(Statement::PrintStatement(value))
} }
} }
fn parse_variable_declaration(&mut self) -> Option<Statement> { fn parse_variable_declaration(&mut self) -> Option<Statement> {
if !self.match_token(Token::Let) { return None; } if !self.match_token(Token::Let) { return None; }
let token_option = self.peek_and_advance(); let token_option = self.peek_and_advance();
if let Some(Token::Identifier(name)) = token_option { if let Some(Token::Identifier(name)) = token_option {
let initializer = if self.match_token(Token::Equal) { let initializer = if self.match_token(Token::Equal) {
@ -426,14 +435,14 @@ impl Parser {
None None
}; };
if self.match_token(Token::Semicolon) { if !self.match_token(Token::Semicolon) {
Some(Statement::VariableDeclaration(name, initializer))
} else {
eprintln!("Error: Expected ';' after variable declaration."); eprintln!("Error: Expected ';' after variable declaration.");
None None
} else {
Some(Statement::VariableDeclaration(name, initializer))
} }
} else { } else {
eprintln!("Error: Expected variable name after 'let'."); eprintln!("Error: Expected variable name after 'let'.");
None None
} }
} }