# allowing aliases to override builtins to support default options 7 messages from 2009-03-06 to 2009-03-07. Participants: Jay Soffian, Sverre Rabbelier, Junio C Hamano, Johannes Schindelin. Thread: https://gitlist.dev/t/18183 ## Jay Soffian, 2009-03-06 22:30 Subject: allowing aliases to override builtins to support default options Message-ID: <76718490903061430s2fbea2dfibe06282fd22b1588@mail.gmail.com> URL: https://gitlist.dev/e/76718490903061430s2fbea2dfibe06282fd22b1588%40mail.gmail.com ``` Currently git does not allow aliases to override builtins. I understand the reasoning behind this, but I wonder if it's overly conservative. Most shells support overriding commands with aliases, and I'm not sure why git needs to be more conservative than the shell. (Although, I will say, I hate when vendors alias rm to "rm -i", etc...) It seems like this would be an elegant way to support default options. Were it to be supported, it should probably have an escape hatch, such as git --no-alias COMMAND, and it should probably only apply to porcelains. Thoughts? j. ``` ## Sverre Rabbelier, 2009-03-06 22:37 Subject: Re: allowing aliases to override builtins to support default options Message-ID: URL: https://gitlist.dev/e/fabb9a1e0903061437t2df5620bn58c6c087214f994b%40mail.gmail.com In-Reply-To: <76718490903061430s2fbea2dfibe06282fd22b1588@mail.gmail.com> ``` Heya, On Fri, Mar 6, 2009 at 23:30, Jay Soffian wrote: > Most shells support overriding commands with aliases, and I'm not sure > why git needs to be more conservative than the shell. (Although, I > will say, I hate when vendors alias rm to "rm -i", etc...) Hmmm, maybe we could require marking such an alias somehow, to signify that you're aware that you're overriding a builtin? Also, what would we do the alias 'foo' calling 'git foo'? Does it call the original command, or itself? -- Cheers, Sverre Rabbelier ``` ## Junio C Hamano, 2009-03-06 23:22 Subject: Re: allowing aliases to override builtins to support default options Message-ID: <7vhc26qls3.fsf@gitster.siamese.dyndns.org> URL: https://gitlist.dev/e/7vhc26qls3.fsf%40gitster.siamese.dyndns.org In-Reply-To: <76718490903061430s2fbea2dfibe06282fd22b1588@mail.gmail.com> ``` Jay Soffian writes: > Currently git does not allow aliases to override builtins. I > understand the reasoning behind this, but I wonder if it's overly > conservative. It is not. > Most shells support overriding commands with aliases, and I'm not sure > why git needs to be more conservative than the shell. Because sane shells do not expand aliases when used in a script, and gives a handy way to defeat the alias even from the command line. $ alias ls='ls -aF' $ echo ls >script $ chmod +x script and compare: $ ./script $ ls $ /bin/ls ``` ## Jay Soffian, 2009-03-06 23:51 Subject: Re: allowing aliases to override builtins to support default options Message-ID: <76718490903061551m24a95ed8r2e334ff0e6f0fcf3@mail.gmail.com> URL: https://gitlist.dev/e/76718490903061551m24a95ed8r2e334ff0e6f0fcf3%40mail.gmail.com In-Reply-To: <7vhc26qls3.fsf@gitster.siamese.dyndns.org> ``` On Fri, Mar 6, 2009 at 6:22 PM, Junio C Hamano wrote: > Because sane shells do not expand aliases when used in a script, and gives > a handy way to defeat the alias even from the command line. > >    $ alias ls='ls -aF' >    $ echo ls >script >    $ chmod +x script > > and compare: > >    $ ./script >    $ ls >    $ /bin/ls Understood. And if git could do the same, still no? j. ``` ## Johannes Schindelin, 2009-03-07 02:37 Subject: Re: allowing aliases to override builtins to support default options Message-ID: URL: https://gitlist.dev/e/alpine.DEB.1.00.0903070336200.10279%40pacific.mpi-cbg.de In-Reply-To: <76718490903061430s2fbea2dfibe06282fd22b1588@mail.gmail.com> ``` Hi, On Fri, 6 Mar 2009, Jay Soffian wrote: > Currently git does not allow aliases to override builtins. I understand > the reasoning behind this, but I wonder if it's overly conservative. > > Most shells support overriding commands with aliases, and I'm not sure > why git needs to be more conservative than the shell. (Although, I will > say, I hate when vendors alias rm to "rm -i", etc...) > > It seems like this would be an elegant way to support default options. What you dream about breaks a lot of scripts. So while it might be nice for you, you would make life of others much, much, much harder. Not nice at all. Ciao, Dscho ``` ## Jay Soffian, 2009-03-07 02:57 Subject: Re: allowing aliases to override builtins to support default options Message-ID: <76718490903061857y5446098by3633559697508c2e@mail.gmail.com> URL: https://gitlist.dev/e/76718490903061857y5446098by3633559697508c2e%40mail.gmail.com In-Reply-To: ``` On Fri, Mar 6, 2009 at 9:37 PM, Johannes Schindelin wrote: > What you dream about breaks a lot of scripts. I said I understood the implications. > So while it might be nice for you, you would make life of others much, > much, much harder.  Not nice at all. This is not something I am dreaming about, and I'm only interested to the extent that it improves git w/o hindering existing users. I'm certainly not aiming to be not nice to anyone! For example, what if: 1. The aliases applied only to porcelain commands, not to plumbing. 2. The aliases worked only if stdout was a terminal, using the same method that git uses for detecting when it is okay to start a pager. 3. git took --alias-builtins and --no-alias-builtins just like it takes --paginate and --no-pager to override (2). j. ``` ## Johannes Schindelin, 2009-03-07 03:10 Subject: Re: allowing aliases to override builtins to support default options Message-ID: URL: https://gitlist.dev/e/alpine.DEB.1.00.0903070407480.10279%40pacific.mpi-cbg.de In-Reply-To: <76718490903061857y5446098by3633559697508c2e@mail.gmail.com> ``` Hi, On Fri, 6 Mar 2009, Jay Soffian wrote: > For example, what if: > > 1. The aliases applied only to porcelain commands, not to plumbing. Inconsistency like this is bad for a couple of reasons. Just 3 out of them: - it makes it hard for users to understand, - it is prone for subtle breakages, - the code will be complicated, and therefore ugly. > 2. The aliases worked only if stdout was a terminal, using the same > method that git uses for detecting when it is okay to start a pager. This would be even more complicated to understand for the regular Git user who just wants to use the darned thing and not care about its internals. > 3. git took --alias-builtins and --no-alias-builtins just like it takes > --paginate and --no-pager to override (2). And this makes it even more complicated. I'd rather stay with our current notion that aliases cannot override Git programs. This is _very_ easy to explain, and also _very_ easy to defend. Ciao, Dscho ```