Re: >= and <= for string comparison

[Ruiyang Peng]

On 2023/1/17 7:55, Peng Yu wrote:
> OK. I never thought about that.
>
> It is functionally equivalent, but not as readable as >= and <=.
>
> For the same logic, for arithmetic operators, we could use ((! (x< y)
> )) and ((! (x > y) )). But there are still >= and <= for arithmetic
> operators. Why don't have >= and <= for strings?
>
> On 1/16/23, Kerin Millar <kfm@plushkava.net> wrote:
> > On Mon, 16 Jan 2023 12:01:12 -0600
> > Peng Yu <pengyu.ut@gmail.com> wrote:
> >
> > > string1 < string2
> > >                True if string1 sorts before string2 lexicographically.
> > >
> > >         string1 > string2
> > >                True if string1 sorts after string2 lexicographically.
> > >
> > > According to the manual, >= and <= are not available for string
> > > comparison. But if >= and <= are available for arithmetic expression.
> > > Why >= and <= can not be introduced for string comparison? Currently,
> > > as a walkaround, I have to use > and = for >=, and < and = for <=. It
> > > is rather cumbersome to write bash code in this way.
> > This is not a response to the question itself but the penultimate 
> > sentence
> > isn't true. [[ ! str1 < str2 ]] and [[ ! str1 > str2 ]] would also do.
> >
> > --
> > Kerin Millar

I think it would be simple to add support for >= and <=, and would also 
unify operations on strings with arithmetic operations.  I haven't 
figured out what problem this could cause just yet.  I think the biggest 
reason why bash didn't add this is that it's not very useful.

--
Ruiyang Peng