Syntax highlighting only matches strings if the character before the opening quotation mark is a letter

Question

I'm writing a syntax file. To highlight strings, I'm defining a region just like it says in the help file:

syn region m2String start=/"/ skip=/\\"/ end=/"/

and later I have:

let b:current_syntax = "m2" hi def link m2String String

However, this isn't behaving the way I want it to. After some experimenting, I figured out that vim is only highlighting strings if the character before the first quotation mark is a letter. Here's a screen shot:

Does anyone know why this is happening and how to fix it? If it helps, I'm using vim version 7.4.1689 in the terminal. My terminal is xterm-256color.

Answer 1

I found the culprit: the original author of this syntax file included the line syn match m2Keyword /\A\+/. I guess this matched the first quotation mark before the string region did.