From 4abade50d7096ee5585255ca08d69b1ccd73d09f Mon Sep 17 00:00:00 2001 From: Manuel Hoffmann Date: Mon, 13 Apr 2015 15:56:10 +0200 Subject: Added a help span which informs the user about the escaping of curly braces in a format string if a wrongly escaped one is detected in a string. --- src/libsyntax/parse/lexer/mod.rs | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'src/libsyntax/parse') diff --git a/src/libsyntax/parse/lexer/mod.rs b/src/libsyntax/parse/lexer/mod.rs index 22b7d5c9f1d..f891318659a 100644 --- a/src/libsyntax/parse/lexer/mod.rs +++ b/src/libsyntax/parse/lexer/mod.rs @@ -843,13 +843,19 @@ impl<'a> StringReader<'a> { if ascii_only { "unknown byte escape" } else { "unknown character escape" }, c); + let sp = codemap::mk_sp(escaped_pos, last_pos); if e == '\r' { - let sp = codemap::mk_sp(escaped_pos, last_pos); self.span_diagnostic.span_help( sp, "this is an isolated carriage return; consider checking \ your editor and version control settings") } + if (e == '{' || e == '}') && !ascii_only { + self.span_diagnostic.span_help( + sp, + "if used in a formatting string, \ + curly braces are escaped with `{{` and `}}`") + } false } } -- cgit 1.4.1-3-g733a5