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Comment by zelphirkalt | Hacker News Reader

The problem with .ONESHELL is, that it is for the whole file. I so wish it was per target. That would be really useful. But for the whole file? Maybe I need each line to be a separate shell anywhere in the file and that will make it impossible to use .ONESHELL for the entire file.

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It is per target, that's how it works when I've used it. For example:

  # Makefile
  SHELL := bash
  .ONESHELL:
  .RECIPEPREFIX = >
  
  thing1:
  > FOO=bar
  > echo "$${FOO:?}"
  .PHONY: thing1
  
  thing2:
  > echo "$${FOO:?}"
  .PHONY: thing2

Results in:

  $ make thing1 thing2
  FOO=bar
  echo "${FOO:?}"
  bar
  echo "${FOO:?}"
  bash: line 1: FOO: parameter null or not set

Note how the bash error for unset FOO is line 1 for the second target.

Edit: Maybe I misinterpreted, do you mean you'd want to choose whether a given target is ONESHELL or not?

> [...] do you mean you'd want to choose whether a given target is ONESHELL or not?

Yep, exactly! I would like to have some targets use ONESHELL and others in the same Makefile not use ONESHELL. So that I can choose the most appropriate for each target.

So far I have managed by avoiding ONESHELL and doing the typical "backslash, next line continues" thingy. But it puts some people off.

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