I would like to set up a few straight alias (without fixed ARGS) for some external executables in Eshell that need access to the command-line ARGS (that will vary). The function eshell-maybe-replace-by-alias is expressly designed to omit the ARGS.

EXAMPLE: The alias file within the Eshell folder [eshell-aliases-file] contains the following entries below. When I call git diff SHA1234567890 > patch.diff, eshell-maybe-replace-by-alias excludes diff SHA1234567890 and the patch file that gets created is a printout from git telling me what types of command line options are possible -- this is because git was called by Eshell without any arguments.

alias git /Users/HOME/.0.data/.0.emacs/.0.macports/bin/git
alias curl /Users/HOME/.0.data/.0.emacs/.0.macports/bin/curl

I hacked the last line of eshell-maybe-replace-by-alias to include the ARGS [i.e., ,(eshell-parse-command (nth 1 alias) args)], but have a feeling that there may be an existing method to better handle this dilemma.

I played around with creating a custom function named eshell/COMMAND, but ran into several problems with with pre/post command hooks needing to be suppressed the first loop; an extra \n that needed to be suppressed the second loop; escaping double-quotes (of strings greater than one word) in order to survive the first loop; and, an unresolved issue when dealing with redirection >. Therefore, the hack of eshell-maybe-replace-by-alias seems the easiest approach so far.

[I feel as though a bug report is not the right avenue at this point because Emacs 26 expressly has the ARGS labeled as _args; i.e., disregard the ARGS.]

  • I don't know much about eshell so I'm not the person to help here, but FWIW I found the question a bit confusing, and suspect that some concrete examples would clarify both the problem, and what you would like to achieve.
    – phils
    Sep 4 '18 at 5:29
  • @phils -- thank you for the constructive help. I added a specific example to the question above.
    – lawlist
    Sep 4 '18 at 6:08
  • If you want to pass arguments to the alias, its definition needs to end in '$*' (the eshell info manual is short but pretty clear)
    – rpluim
    Sep 4 '18 at 8:17

According to @rpluim's comment and (eshell) Aliases:

Note that unlike aliases in Bash, arguments must be handled explicitly.

Here is the way to create an alias to git:

$ alias git '/usr/local/bin/git $*'

The above Eshell command will write the following to eshell-aliases-file:

alias git /usr/local/bin/git $*

BTW, as you can see Eshell command line and eshell-aliases-file don't use the exactly same syntax (i.e, the quote), and the difference does matter according to my test. This is weird,

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