Re: test -lt inconsistent about white space

[Paul Eggert]

On 2023-10-28 18:41, Oğuz wrote:
> Why? The same commands fail on bosh, yash, and zsh too.

I don't know what bosh is. zsh and yash prohibit trailing spaces in 
integers, but allow leading spaces:

  % test ' 3' -lt ' 4'
  % test ' 3 ' -lt ' 4 '
  test: integer expression expected:  3

Presumably this is because they use strtol or equivalent, and accept 
exactly the strings that strtol accepts. Although that's an allowed 
behavior, it's not the behavior that Bash and ksh and Dash use; they 
both allow the second example listed above.

My understanding is that Bash was intended to allow both leading and 
trailing whitespace. This is compatible with ksh and with Dash. If 
that's the intent, Bash should be consistent about it, just as ksh and 
Dash are. There seems little point to allowing one nonempty set of 
whitespace characters before the integer, and a different nonempty set 
of whitespace characters afterwards.

For what it's worth, 7th Edition Unix sh allows any characters after the 
integer. (There doesn't even have to be an integer!)

PS. As I understand it, POSIX allows all the behaviors described above, 
so this is not a POSIX conformance issue.