50 lines
1.2 KiB
Rust
50 lines
1.2 KiB
Rust
extern crate proc_macro2;
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extern crate syn;
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extern crate syntax;
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extern crate syntax_pos;
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use self::syntax::ast;
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use self::syntax::parse::{self, ParseSess};
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use self::syntax::ptr::P;
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use self::syntax::source_map::FilePathMapping;
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use self::syntax_pos::FileName;
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use std::panic;
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pub fn libsyntax_expr(input: &str) -> Option<P<ast::Expr>> {
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match panic::catch_unwind(|| {
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let sess = ParseSess::new(FilePathMapping::empty());
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sess.span_diagnostic.set_continue_after_error(false);
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let e = parse::new_parser_from_source_str(
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&sess,
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FileName::Custom("test_precedence".to_string()),
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input.to_string(),
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)
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.parse_expr();
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match e {
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Ok(expr) => Some(expr),
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Err(mut diagnostic) => {
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diagnostic.emit();
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None
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}
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}
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}) {
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Ok(Some(e)) => Some(e),
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Ok(None) => None,
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Err(_) => {
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errorf!("libsyntax panicked\n");
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None
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}
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}
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}
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pub fn syn_expr(input: &str) -> Option<syn::Expr> {
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match syn::parse_str(input) {
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Ok(e) => Some(e),
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Err(msg) => {
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errorf!("syn failed to parse\n{:?}\n", msg);
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None
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}
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}
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}
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