blob: 6ebfab3a133ef80da61e6f8d75be0c8afa8314c4 [file] [log] [blame]
//! Routines the parser uses to classify AST nodes
// Predicates on exprs and stmts that the pretty-printer and parser use
use crate::ast;
/// Does this expression require a semicolon to be treated
/// as a statement? The negation of this: 'can this expression
/// be used as a statement without a semicolon' -- is used
/// as an early-bail-out in the parser so that, for instance,
/// if true {...} else {...}
/// |x| 5
/// isn't parsed as (if true {...} else {...} | x) | 5
pub fn expr_requires_semi_to_be_stmt(e: &ast::Expr) -> bool {
match e.node {
ast::ExprKind::If(..) |
ast::ExprKind::Match(..) |
ast::ExprKind::Block(..) |
ast::ExprKind::While(..) |
ast::ExprKind::Loop(..) |
ast::ExprKind::ForLoop(..) |
ast::ExprKind::TryBlock(..) => false,
_ => true,
}
}