From f75da83a60047c1a32e1baf50ef6b6f57d7148c6 Mon Sep 17 00:00:00 2001
From: Coleman McFarland <coleman.mcfarland@gmail.com>
Date: Mon, 16 Apr 2018 01:06:19 -0700
Subject: [PATCH] Pre-allocate sufficient size for our output String
---
maud_macros/src/lib.rs | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)
diff --git a/maud_macros/src/lib.rs b/maud_macros/src/lib.rs
index 0a5f2be..1755f9d 100644
--- a/maud_macros/src/lib.rs
+++ b/maud_macros/src/lib.rs
@@ -10,7 +10,7 @@ extern crate proc_macro;
mod parse;
mod build;
-use proc_macro::{Span, Term, TokenStream, TokenTree};
+use proc_macro::{Literal, Span, Term, TokenStream, TokenTree};
use proc_macro::quote;
type ParseResult<T> = Result<T, String>;
@@ -32,17 +32,15 @@ fn expand(input: TokenStream) -> TokenStream {
let output_ident = TokenTree::Term(Term::new("__maud_output", Span::def_site()));
// Heuristic: the size of the resulting markup tends to correlate with the
// code size of the template itself
- //
- // NOTE: can't get this to compile inside quote!
- //let size_hint = Literal::u64_unsuffixed(size_hint as u64);
+ let size_hint = input.to_string().len();
+ let size_hint = TokenTree::Literal(Literal::u64_unsuffixed(size_hint as u64));
let stmts = match parse::parse(input, output_ident.clone()) {
Ok(stmts) => stmts,
Err(e) => panic!(e),
};
quote!({
extern crate maud;
- //let mut $output_ident = String::with_capacity($size_hint as usize);
- let mut $output_ident = String::new();
+ let mut $output_ident = String::with_capacity($size_hint as usize);
$stmts
maud::PreEscaped($output_ident)
})