| //! 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::IfLet(..) | |
| ast::ExprKind::Match(..) | |
| ast::ExprKind::Block(..) | |
| ast::ExprKind::While(..) | |
| ast::ExprKind::WhileLet(..) | |
| ast::ExprKind::Loop(..) | |
| ast::ExprKind::ForLoop(..) | |
| ast::ExprKind::TryBlock(..) => false, |
| _ => true, |
| } |
| } |
