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Comment by gruseom | Hacker News Reader

I haven't been able to figure out how to match a one-sided word boundary using git-grep. For example, say a file includes the word "router". You can do this to match the exact word:

  git grep -w router

But what if you want to match just the word boundary at the start ("rout") or at the end ("outer")?

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The "--perl-regexp" flag to git grep enables perl flavored regexes, which contain explicit word boundary matching. To match only word starts, you could use the following:

    git grep --perl-regexp "\brout"

and for just word endings

    git grep --perl-regexp "outer\b"

This doesn't work for me, nor do the other two users' suggestions. I even just rebuilt git in case my version was out of date.

Are you using homebrew?

  $ brew info git 
  git: stable 1.8.3.2, HEAD
  http://git-scm.com
  /usr/local/Cellar/git/HEAD (1324 files, 29M) *
    Built from source with: --with-blk-sha1 --with-pcre
  From: https://github.com/mxcl/homebrew/commits/master/Library/Formula/git.rb
  ==> Dependencies
  Optional: pcre, gettext
  ==> Options
  --with-blk-sha1
	Compile with the block-optimized SHA1 implementation
  --with-gettext
	Build with gettext support
  --with-pcre
	Build with pcre support
  --without-completions
	Disable bash/zsh completions from "contrib" directory

What does "built from source with" say?

I don't use homebrew, but your comment made me realize what I needed to do to successfully compile git with pcre. As a result, this now works:

  git grep -P "outer\b"

Yay! Thank you and moonboots.

This is an important feature for me, because I organize my code lexically (primarily by being disciplined about using unique names for things) and rely on grep to quickly find what I want. Occasionally one unique name overlaps with another, and then I really want to match the word boundary.

The standard grep symbols for beginning and end of word are \< and \>

So try those. (I don't have a git repo handy to test)

(edit: I tested and it works)

git grep -E '\brout|outer\b'

Are you sure this works? I've tried it many times.

git grep '\<rout'

This is the syntax I use in Emacs, so I would love it if git-grep would do the same. But it doesn't, for me. Are you sure that it does for you?

Works for me (git 1.7.7.6)

https://news.ycombinator.com/item?id=6017401

Huh. How annoying that it doesn't just work everywhere. Annoying in two ways, actually: one, I want it to work; two, it bugs me not to understand what's going on.

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