Move built-in syntax extensions to a separate crate
This commit is contained in:
Seo Sanghyeon
716
src/libsyntax_ext/format.rs
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716
src/libsyntax_ext/format.rs
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@@ -0,0 +1,716 @@
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// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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use self::ArgumentType::*;
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use self::Position::*;
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use fmt_macros as parse;
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use syntax::ast;
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use syntax::codemap::{Span, respan};
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use syntax::ext::base::*;
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use syntax::ext::base;
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use syntax::ext::build::AstBuilder;
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use syntax::fold::Folder;
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use syntax::parse::token::special_idents;
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use syntax::parse::token;
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use syntax::ptr::P;
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use std::collections::HashMap;
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#[derive(PartialEq)]
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enum ArgumentType {
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Known(String),
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Unsigned
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}
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enum Position {
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Exact(usize),
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Named(String),
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}
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struct Context<'a, 'b:'a> {
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ecx: &'a mut ExtCtxt<'b>,
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/// The macro's call site. References to unstable formatting internals must
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/// use this span to pass the stability checker.
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macsp: Span,
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/// The span of the format string literal.
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fmtsp: Span,
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/// Parsed argument expressions and the types that we've found so far for
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/// them.
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args: Vec<P<ast::Expr>>,
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arg_types: Vec<Option<ArgumentType>>,
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/// Parsed named expressions and the types that we've found for them so far.
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/// Note that we keep a side-array of the ordering of the named arguments
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/// found to be sure that we can translate them in the same order that they
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/// were declared in.
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names: HashMap<String, P<ast::Expr>>,
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name_types: HashMap<String, ArgumentType>,
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name_ordering: Vec<String>,
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/// The latest consecutive literal strings, or empty if there weren't any.
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literal: String,
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/// Collection of the compiled `rt::Argument` structures
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pieces: Vec<P<ast::Expr>>,
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/// Collection of string literals
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str_pieces: Vec<P<ast::Expr>>,
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/// Stays `true` if all formatting parameters are default (as in "{}{}").
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all_pieces_simple: bool,
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name_positions: HashMap<String, usize>,
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/// Updated as arguments are consumed or methods are entered
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nest_level: usize,
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next_arg: usize,
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}
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/// Parses the arguments from the given list of tokens, returning None
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/// if there's a parse error so we can continue parsing other format!
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/// expressions.
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///
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/// If parsing succeeds, the return value is:
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/// ```ignore
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/// Some((fmtstr, unnamed arguments, ordering of named arguments,
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/// named arguments))
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/// ```
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fn parse_args(ecx: &mut ExtCtxt, sp: Span, tts: &[ast::TokenTree])
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-> Option<(P<ast::Expr>, Vec<P<ast::Expr>>, Vec<String>,
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HashMap<String, P<ast::Expr>>)> {
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let mut args = Vec::new();
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let mut names = HashMap::<String, P<ast::Expr>>::new();
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let mut order = Vec::new();
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let mut p = ecx.new_parser_from_tts(tts);
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if p.token == token::Eof {
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ecx.span_err(sp, "requires at least a format string argument");
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return None;
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}
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let fmtstr = panictry!(p.parse_expr());
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let mut named = false;
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while p.token != token::Eof {
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if !panictry!(p.eat(&token::Comma)) {
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ecx.span_err(sp, "expected token: `,`");
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return None;
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}
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if p.token == token::Eof { break } // accept trailing commas
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if named || (p.token.is_ident() && p.look_ahead(1, |t| *t == token::Eq)) {
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named = true;
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let ident = match p.token {
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token::Ident(i, _) => {
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panictry!(p.bump());
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i
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}
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_ if named => {
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ecx.span_err(p.span,
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"expected ident, positional arguments \
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cannot follow named arguments");
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return None;
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}
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_ => {
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ecx.span_err(p.span,
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&format!("expected ident for named argument, found `{}`",
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p.this_token_to_string()));
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return None;
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}
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};
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let name: &str = &ident.name.as_str();
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panictry!(p.expect(&token::Eq));
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let e = panictry!(p.parse_expr());
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match names.get(name) {
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None => {}
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Some(prev) => {
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ecx.span_err(e.span,
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&format!("duplicate argument named `{}`",
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name));
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ecx.parse_sess.span_diagnostic.span_note(prev.span, "previously here");
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continue
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}
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}
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order.push(name.to_string());
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names.insert(name.to_string(), e);
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} else {
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args.push(panictry!(p.parse_expr()));
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}
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}
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Some((fmtstr, args, order, names))
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}
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impl<'a, 'b> Context<'a, 'b> {
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/// Verifies one piece of a parse string. All errors are not emitted as
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/// fatal so we can continue giving errors about this and possibly other
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/// format strings.
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fn verify_piece(&mut self, p: &parse::Piece) {
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match *p {
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parse::String(..) => {}
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parse::NextArgument(ref arg) => {
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// width/precision first, if they have implicit positional
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// parameters it makes more sense to consume them first.
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self.verify_count(arg.format.width);
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self.verify_count(arg.format.precision);
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// argument second, if it's an implicit positional parameter
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// it's written second, so it should come after width/precision.
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let pos = match arg.position {
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parse::ArgumentNext => {
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let i = self.next_arg;
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if self.check_positional_ok() {
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self.next_arg += 1;
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}
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Exact(i)
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}
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parse::ArgumentIs(i) => Exact(i),
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parse::ArgumentNamed(s) => Named(s.to_string()),
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};
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let ty = Known(arg.format.ty.to_string());
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self.verify_arg_type(pos, ty);
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}
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}
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}
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fn verify_count(&mut self, c: parse::Count) {
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match c {
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parse::CountImplied | parse::CountIs(..) => {}
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parse::CountIsParam(i) => {
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self.verify_arg_type(Exact(i), Unsigned);
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}
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parse::CountIsName(s) => {
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self.verify_arg_type(Named(s.to_string()), Unsigned);
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}
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parse::CountIsNextParam => {
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if self.check_positional_ok() {
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let next_arg = self.next_arg;
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self.verify_arg_type(Exact(next_arg), Unsigned);
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self.next_arg += 1;
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}
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}
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}
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}
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fn check_positional_ok(&mut self) -> bool {
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if self.nest_level != 0 {
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self.ecx.span_err(self.fmtsp, "cannot use implicit positional \
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arguments nested inside methods");
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false
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} else {
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true
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}
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}
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fn describe_num_args(&self) -> String {
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match self.args.len() {
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0 => "no arguments given".to_string(),
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1 => "there is 1 argument".to_string(),
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x => format!("there are {} arguments", x),
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}
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}
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fn verify_arg_type(&mut self, arg: Position, ty: ArgumentType) {
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match arg {
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Exact(arg) => {
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if self.args.len() <= arg {
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let msg = format!("invalid reference to argument `{}` ({})",
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arg, self.describe_num_args());
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self.ecx.span_err(self.fmtsp, &msg[..]);
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return;
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}
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{
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let arg_type = match self.arg_types[arg] {
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None => None,
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Some(ref x) => Some(x)
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};
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self.verify_same(self.args[arg].span, &ty, arg_type);
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}
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if self.arg_types[arg].is_none() {
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self.arg_types[arg] = Some(ty);
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}
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}
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Named(name) => {
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let span = match self.names.get(&name) {
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Some(e) => e.span,
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None => {
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let msg = format!("there is no argument named `{}`", name);
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self.ecx.span_err(self.fmtsp, &msg[..]);
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return;
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}
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};
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self.verify_same(span, &ty, self.name_types.get(&name));
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if !self.name_types.contains_key(&name) {
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self.name_types.insert(name.clone(), ty);
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}
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// Assign this named argument a slot in the arguments array if
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// it hasn't already been assigned a slot.
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if !self.name_positions.contains_key(&name) {
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let slot = self.name_positions.len();
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self.name_positions.insert(name, slot);
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}
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}
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}
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}
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/// When we're keeping track of the types that are declared for certain
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/// arguments, we assume that `None` means we haven't seen this argument
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/// yet, `Some(None)` means that we've seen the argument, but no format was
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/// specified, and `Some(Some(x))` means that the argument was declared to
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/// have type `x`.
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///
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/// Obviously `Some(Some(x)) != Some(Some(y))`, but we consider it true
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/// that: `Some(None) == Some(Some(x))`
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fn verify_same(&self,
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sp: Span,
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ty: &ArgumentType,
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before: Option<&ArgumentType>) {
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let cur = match before {
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None => return,
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Some(t) => t,
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};
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if *ty == *cur {
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return
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}
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match (cur, ty) {
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(&Known(ref cur), &Known(ref ty)) => {
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self.ecx.span_err(sp,
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&format!("argument redeclared with type `{}` when \
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it was previously `{}`",
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*ty,
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*cur));
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}
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(&Known(ref cur), _) => {
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self.ecx.span_err(sp,
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&format!("argument used to format with `{}` was \
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attempted to not be used for formatting",
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*cur));
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}
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(_, &Known(ref ty)) => {
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self.ecx.span_err(sp,
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&format!("argument previously used as a format \
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argument attempted to be used as `{}`",
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*ty));
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}
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(_, _) => {
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self.ecx.span_err(sp, "argument declared with multiple formats");
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}
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}
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}
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fn rtpath(ecx: &ExtCtxt, s: &str) -> Vec<ast::Ident> {
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ecx.std_path(&["fmt", "rt", "v1", s])
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}
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fn trans_count(&self, c: parse::Count) -> P<ast::Expr> {
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let sp = self.macsp;
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let count = |c, arg| {
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let mut path = Context::rtpath(self.ecx, "Count");
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path.push(self.ecx.ident_of(c));
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match arg {
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Some(arg) => self.ecx.expr_call_global(sp, path, vec![arg]),
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None => self.ecx.expr_path(self.ecx.path_global(sp, path)),
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}
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};
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match c {
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parse::CountIs(i) => count("Is", Some(self.ecx.expr_usize(sp, i))),
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parse::CountIsParam(i) => {
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count("Param", Some(self.ecx.expr_usize(sp, i)))
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}
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parse::CountImplied => count("Implied", None),
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parse::CountIsNextParam => count("NextParam", None),
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parse::CountIsName(n) => {
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let i = match self.name_positions.get(n) {
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Some(&i) => i,
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None => 0, // error already emitted elsewhere
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};
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let i = i + self.args.len();
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count("Param", Some(self.ecx.expr_usize(sp, i)))
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}
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}
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}
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/// Translate the accumulated string literals to a literal expression
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fn trans_literal_string(&mut self) -> P<ast::Expr> {
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let sp = self.fmtsp;
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let s = token::intern_and_get_ident(&self.literal);
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self.literal.clear();
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self.ecx.expr_str(sp, s)
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}
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/// Translate a `parse::Piece` to a static `rt::Argument` or append
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/// to the `literal` string.
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fn trans_piece(&mut self, piece: &parse::Piece) -> Option<P<ast::Expr>> {
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let sp = self.macsp;
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match *piece {
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parse::String(s) => {
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self.literal.push_str(s);
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None
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}
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parse::NextArgument(ref arg) => {
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// Translate the position
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let pos = {
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let pos = |c, arg| {
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let mut path = Context::rtpath(self.ecx, "Position");
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path.push(self.ecx.ident_of(c));
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match arg {
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Some(i) => {
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let arg = self.ecx.expr_usize(sp, i);
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self.ecx.expr_call_global(sp, path, vec![arg])
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}
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None => {
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self.ecx.expr_path(self.ecx.path_global(sp, path))
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}
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}
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};
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match arg.position {
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// These two have a direct mapping
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parse::ArgumentNext => pos("Next", None),
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parse::ArgumentIs(i) => pos("At", Some(i)),
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// Named arguments are converted to positional arguments
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// at the end of the list of arguments
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parse::ArgumentNamed(n) => {
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let i = match self.name_positions.get(n) {
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Some(&i) => i,
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None => 0, // error already emitted elsewhere
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};
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let i = i + self.args.len();
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pos("At", Some(i))
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}
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}
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};
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let simple_arg = parse::Argument {
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position: parse::ArgumentNext,
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format: parse::FormatSpec {
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fill: arg.format.fill,
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align: parse::AlignUnknown,
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flags: 0,
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precision: parse::CountImplied,
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width: parse::CountImplied,
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ty: arg.format.ty
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}
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};
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let fill = match arg.format.fill { Some(c) => c, None => ' ' };
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if *arg != simple_arg || fill != ' ' {
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self.all_pieces_simple = false;
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}
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// Translate the format
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let fill = self.ecx.expr_lit(sp, ast::LitChar(fill));
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let align = |name| {
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let mut p = Context::rtpath(self.ecx, "Alignment");
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p.push(self.ecx.ident_of(name));
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self.ecx.path_global(sp, p)
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};
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let align = match arg.format.align {
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parse::AlignLeft => align("Left"),
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parse::AlignRight => align("Right"),
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parse::AlignCenter => align("Center"),
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parse::AlignUnknown => align("Unknown"),
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};
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let align = self.ecx.expr_path(align);
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let flags = self.ecx.expr_u32(sp, arg.format.flags);
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let prec = self.trans_count(arg.format.precision);
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let width = self.trans_count(arg.format.width);
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let path = self.ecx.path_global(sp, Context::rtpath(self.ecx, "FormatSpec"));
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let fmt = self.ecx.expr_struct(sp, path, vec!(
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self.ecx.field_imm(sp, self.ecx.ident_of("fill"), fill),
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self.ecx.field_imm(sp, self.ecx.ident_of("align"), align),
|
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self.ecx.field_imm(sp, self.ecx.ident_of("flags"), flags),
|
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self.ecx.field_imm(sp, self.ecx.ident_of("precision"), prec),
|
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self.ecx.field_imm(sp, self.ecx.ident_of("width"), width)));
|
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let path = self.ecx.path_global(sp, Context::rtpath(self.ecx, "Argument"));
|
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Some(self.ecx.expr_struct(sp, path, vec!(
|
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self.ecx.field_imm(sp, self.ecx.ident_of("position"), pos),
|
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self.ecx.field_imm(sp, self.ecx.ident_of("format"), fmt))))
|
||||
}
|
||||
}
|
||||
}
|
||||
|
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fn static_array(ecx: &mut ExtCtxt,
|
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name: &str,
|
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piece_ty: P<ast::Ty>,
|
||||
pieces: Vec<P<ast::Expr>>)
|
||||
-> P<ast::Expr> {
|
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let sp = piece_ty.span;
|
||||
let ty = ecx.ty_rptr(sp,
|
||||
ecx.ty(sp, ast::TyVec(piece_ty)),
|
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Some(ecx.lifetime(sp, special_idents::static_lifetime.name)),
|
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ast::MutImmutable);
|
||||
let slice = ecx.expr_vec_slice(sp, pieces);
|
||||
// static instead of const to speed up codegen by not requiring this to be inlined
|
||||
let st = ast::ItemStatic(ty, ast::MutImmutable, slice);
|
||||
|
||||
let name = ecx.ident_of(name);
|
||||
let item = ecx.item(sp, name, vec![], st);
|
||||
let decl = respan(sp, ast::DeclItem(item));
|
||||
|
||||
// Wrap the declaration in a block so that it forms a single expression.
|
||||
ecx.expr_block(ecx.block(sp,
|
||||
vec![P(respan(sp, ast::StmtDecl(P(decl), ast::DUMMY_NODE_ID)))],
|
||||
Some(ecx.expr_ident(sp, name))))
|
||||
}
|
||||
|
||||
/// Actually builds the expression which the iformat! block will be expanded
|
||||
/// to
|
||||
fn into_expr(mut self) -> P<ast::Expr> {
|
||||
let mut locals = Vec::new();
|
||||
let mut names = vec![None; self.name_positions.len()];
|
||||
let mut pats = Vec::new();
|
||||
let mut heads = Vec::new();
|
||||
|
||||
// First, build up the static array which will become our precompiled
|
||||
// format "string"
|
||||
let static_lifetime = self.ecx.lifetime(self.fmtsp, special_idents::static_lifetime.name);
|
||||
let piece_ty = self.ecx.ty_rptr(
|
||||
self.fmtsp,
|
||||
self.ecx.ty_ident(self.fmtsp, self.ecx.ident_of("str")),
|
||||
Some(static_lifetime),
|
||||
ast::MutImmutable);
|
||||
let pieces = Context::static_array(self.ecx,
|
||||
"__STATIC_FMTSTR",
|
||||
piece_ty,
|
||||
self.str_pieces);
|
||||
|
||||
|
||||
// Right now there is a bug such that for the expression:
|
||||
// foo(bar(&1))
|
||||
// the lifetime of `1` doesn't outlast the call to `bar`, so it's not
|
||||
// valid for the call to `foo`. To work around this all arguments to the
|
||||
// format! string are shoved into locals. Furthermore, we shove the address
|
||||
// of each variable because we don't want to move out of the arguments
|
||||
// passed to this function.
|
||||
for (i, e) in self.args.into_iter().enumerate() {
|
||||
let arg_ty = match self.arg_types[i].as_ref() {
|
||||
Some(ty) => ty,
|
||||
None => continue // error already generated
|
||||
};
|
||||
|
||||
let name = self.ecx.ident_of(&format!("__arg{}", i));
|
||||
pats.push(self.ecx.pat_ident(e.span, name));
|
||||
locals.push(Context::format_arg(self.ecx, self.macsp, e.span, arg_ty,
|
||||
self.ecx.expr_ident(e.span, name)));
|
||||
heads.push(self.ecx.expr_addr_of(e.span, e));
|
||||
}
|
||||
for name in &self.name_ordering {
|
||||
let e = match self.names.remove(name) {
|
||||
Some(e) => e,
|
||||
None => continue
|
||||
};
|
||||
let arg_ty = match self.name_types.get(name) {
|
||||
Some(ty) => ty,
|
||||
None => continue
|
||||
};
|
||||
|
||||
let lname = self.ecx.ident_of(&format!("__arg{}",
|
||||
*name));
|
||||
pats.push(self.ecx.pat_ident(e.span, lname));
|
||||
names[*self.name_positions.get(name).unwrap()] =
|
||||
Some(Context::format_arg(self.ecx, self.macsp, e.span, arg_ty,
|
||||
self.ecx.expr_ident(e.span, lname)));
|
||||
heads.push(self.ecx.expr_addr_of(e.span, e));
|
||||
}
|
||||
|
||||
// Now create a vector containing all the arguments
|
||||
let args = locals.into_iter().chain(names.into_iter().map(|a| a.unwrap()));
|
||||
|
||||
let args_array = self.ecx.expr_vec(self.fmtsp, args.collect());
|
||||
|
||||
// Constructs an AST equivalent to:
|
||||
//
|
||||
// match (&arg0, &arg1) {
|
||||
// (tmp0, tmp1) => args_array
|
||||
// }
|
||||
//
|
||||
// It was:
|
||||
//
|
||||
// let tmp0 = &arg0;
|
||||
// let tmp1 = &arg1;
|
||||
// args_array
|
||||
//
|
||||
// Because of #11585 the new temporary lifetime rule, the enclosing
|
||||
// statements for these temporaries become the let's themselves.
|
||||
// If one or more of them are RefCell's, RefCell borrow() will also
|
||||
// end there; they don't last long enough for args_array to use them.
|
||||
// The match expression solves the scope problem.
|
||||
//
|
||||
// Note, it may also very well be transformed to:
|
||||
//
|
||||
// match arg0 {
|
||||
// ref tmp0 => {
|
||||
// match arg1 => {
|
||||
// ref tmp1 => args_array } } }
|
||||
//
|
||||
// But the nested match expression is proved to perform not as well
|
||||
// as series of let's; the first approach does.
|
||||
let pat = self.ecx.pat_tuple(self.fmtsp, pats);
|
||||
let arm = self.ecx.arm(self.fmtsp, vec!(pat), args_array);
|
||||
let head = self.ecx.expr(self.fmtsp, ast::ExprTup(heads));
|
||||
let result = self.ecx.expr_match(self.fmtsp, head, vec!(arm));
|
||||
|
||||
let args_slice = self.ecx.expr_addr_of(self.fmtsp, result);
|
||||
|
||||
// Now create the fmt::Arguments struct with all our locals we created.
|
||||
let (fn_name, fn_args) = if self.all_pieces_simple {
|
||||
("new_v1", vec![pieces, args_slice])
|
||||
} else {
|
||||
// Build up the static array which will store our precompiled
|
||||
// nonstandard placeholders, if there are any.
|
||||
let piece_ty = self.ecx.ty_path(self.ecx.path_global(
|
||||
self.macsp,
|
||||
Context::rtpath(self.ecx, "Argument")));
|
||||
let fmt = Context::static_array(self.ecx,
|
||||
"__STATIC_FMTARGS",
|
||||
piece_ty,
|
||||
self.pieces);
|
||||
|
||||
("new_v1_formatted", vec![pieces, args_slice, fmt])
|
||||
};
|
||||
|
||||
let path = self.ecx.std_path(&["fmt", "Arguments", fn_name]);
|
||||
self.ecx.expr_call_global(self.macsp, path, fn_args)
|
||||
}
|
||||
|
||||
fn format_arg(ecx: &ExtCtxt, macsp: Span, sp: Span,
|
||||
ty: &ArgumentType, arg: P<ast::Expr>)
|
||||
-> P<ast::Expr> {
|
||||
let trait_ = match *ty {
|
||||
Known(ref tyname) => {
|
||||
match &tyname[..] {
|
||||
"" => "Display",
|
||||
"?" => "Debug",
|
||||
"e" => "LowerExp",
|
||||
"E" => "UpperExp",
|
||||
"o" => "Octal",
|
||||
"p" => "Pointer",
|
||||
"b" => "Binary",
|
||||
"x" => "LowerHex",
|
||||
"X" => "UpperHex",
|
||||
_ => {
|
||||
ecx.span_err(sp,
|
||||
&format!("unknown format trait `{}`",
|
||||
*tyname));
|
||||
"Dummy"
|
||||
}
|
||||
}
|
||||
}
|
||||
Unsigned => {
|
||||
let path = ecx.std_path(&["fmt", "ArgumentV1", "from_usize"]);
|
||||
return ecx.expr_call_global(macsp, path, vec![arg])
|
||||
}
|
||||
};
|
||||
|
||||
let path = ecx.std_path(&["fmt", trait_, "fmt"]);
|
||||
let format_fn = ecx.path_global(sp, path);
|
||||
let path = ecx.std_path(&["fmt", "ArgumentV1", "new"]);
|
||||
ecx.expr_call_global(macsp, path, vec![arg, ecx.expr_path(format_fn)])
|
||||
}
|
||||
}
|
||||
|
||||
pub fn expand_format_args<'cx>(ecx: &'cx mut ExtCtxt, sp: Span,
|
||||
tts: &[ast::TokenTree])
|
||||
-> Box<base::MacResult+'cx> {
|
||||
|
||||
match parse_args(ecx, sp, tts) {
|
||||
Some((efmt, args, order, names)) => {
|
||||
MacEager::expr(expand_preparsed_format_args(ecx, sp, efmt,
|
||||
args, order, names))
|
||||
}
|
||||
None => DummyResult::expr(sp)
|
||||
}
|
||||
}
|
||||
|
||||
/// Take the various parts of `format_args!(efmt, args..., name=names...)`
|
||||
/// and construct the appropriate formatting expression.
|
||||
pub fn expand_preparsed_format_args(ecx: &mut ExtCtxt, sp: Span,
|
||||
efmt: P<ast::Expr>,
|
||||
args: Vec<P<ast::Expr>>,
|
||||
name_ordering: Vec<String>,
|
||||
names: HashMap<String, P<ast::Expr>>)
|
||||
-> P<ast::Expr> {
|
||||
let arg_types: Vec<_> = (0..args.len()).map(|_| None).collect();
|
||||
let macsp = ecx.call_site();
|
||||
// Expand the format literal so that efmt.span will have a backtrace. This
|
||||
// is essential for locating a bug when the format literal is generated in
|
||||
// a macro. (e.g. println!("{}"), which uses concat!($fmt, "\n")).
|
||||
let efmt = ecx.expander().fold_expr(efmt);
|
||||
let mut cx = Context {
|
||||
ecx: ecx,
|
||||
args: args,
|
||||
arg_types: arg_types,
|
||||
names: names,
|
||||
name_positions: HashMap::new(),
|
||||
name_types: HashMap::new(),
|
||||
name_ordering: name_ordering,
|
||||
nest_level: 0,
|
||||
next_arg: 0,
|
||||
literal: String::new(),
|
||||
pieces: Vec::new(),
|
||||
str_pieces: Vec::new(),
|
||||
all_pieces_simple: true,
|
||||
macsp: macsp,
|
||||
fmtsp: efmt.span,
|
||||
};
|
||||
let fmt = match expr_to_string(cx.ecx,
|
||||
efmt,
|
||||
"format argument must be a string literal.") {
|
||||
Some((fmt, _)) => fmt,
|
||||
None => return DummyResult::raw_expr(sp)
|
||||
};
|
||||
|
||||
let mut parser = parse::Parser::new(&fmt);
|
||||
|
||||
loop {
|
||||
match parser.next() {
|
||||
Some(piece) => {
|
||||
if !parser.errors.is_empty() { break }
|
||||
cx.verify_piece(&piece);
|
||||
match cx.trans_piece(&piece) {
|
||||
Some(piece) => {
|
||||
let s = cx.trans_literal_string();
|
||||
cx.str_pieces.push(s);
|
||||
cx.pieces.push(piece);
|
||||
}
|
||||
None => {}
|
||||
}
|
||||
}
|
||||
None => break
|
||||
}
|
||||
}
|
||||
if !parser.errors.is_empty() {
|
||||
cx.ecx.span_err(cx.fmtsp, &format!("invalid format string: {}",
|
||||
parser.errors.remove(0)));
|
||||
return DummyResult::raw_expr(sp);
|
||||
}
|
||||
if !cx.literal.is_empty() {
|
||||
let s = cx.trans_literal_string();
|
||||
cx.str_pieces.push(s);
|
||||
}
|
||||
|
||||
// Make sure that all arguments were used and all arguments have types.
|
||||
for (i, ty) in cx.arg_types.iter().enumerate() {
|
||||
if ty.is_none() {
|
||||
cx.ecx.span_err(cx.args[i].span, "argument never used");
|
||||
}
|
||||
}
|
||||
for (name, e) in &cx.names {
|
||||
if !cx.name_types.contains_key(name) {
|
||||
cx.ecx.span_err(e.span, "named argument never used");
|
||||
}
|
||||
}
|
||||
|
||||
cx.into_expr()
|
||||
}
|
||||
Reference in New Issue
Block a user