How to disable a zsh special variable (bang tilde !~)?

Question

My zsh is replacing !~ with a command I previously ran. This is a problem because when I run awk '$1 !~ /abc/, it replaces the !~ with the command.

Any idea on how to disable this? It's possible it's not zsh's fault, but after googling for an hour and not finding anything I decided it was the most likely candidate.

UPDATE:

This only happens when !~ occurs on a newline:

echo !~
# ~/bin/test_translate.rb

echo foo | awk '
$1 !~ /abc/'

awk: cmd. line:2:     $1 ~/bin/test_translate.rb /abc/
awk: cmd. line:2:                            ^ syntax error
awk: cmd. line:3:     $1 ~/bin/test_translate.rb /abc/
awk: cmd. line:3:                                     ^ unexpected newline or end of string

UPDATE 2:

I've narrowed it down to this line in my .zshrc:

source $ZSH/oh-my-zsh.sh

I would like to find out what option is making zsh replace !~ plus spacebar into the last path I accessed, but I don't want to stop using oh-my-zsh. I haven't manually modified $ZSH/oh-my-zsh.sh.

Answer 1

In zsh (and some other shells) ! triggers the history expansion (see man zshexpn section "HISTORY EXPANSION"). In the case of !~ zsh will look for the most recent command starting with ~.

If you do not use history expansion in any way, you can just disable it by adding this to your .zshrc

setopt nobanghist

---

Usually history expansion is not done inside single quoted strings, so it should not affect your awk command in any way:

$ echo !~
~/docs
$ echo foo | awk '
$1 !~ /abc/'            
foo

On the other hand, inside double quotes history expansion is done and you get the mentioned error message:

$ echo !~
~/docs
$ echo foo | awk "
$1 !~ /abc/"   
echo foo | awk "
$1 ~/docs /abc/"
awk: cmd. line:2:  ~/docs /abc/
awk: cmd. line:2:  ^ syntax error
awk: cmd. line:3:  ~/docs /abc/
awk: cmd. line:3:              ^ unexpected newline or end of string

So, if the problem can be traced to source $ZSH/oh-my-zsh.sh, I'd guess that Oh, my ZSH does something to break the way zsh handles quoting.