mirror of
https://github.com/fish-shell/fish-shell.git
synced 2024-12-01 15:14:26 +08:00
59 lines
1.8 KiB
ReStructuredText
59 lines
1.8 KiB
ReStructuredText
string-collect - join strings into one
|
|
======================================
|
|
|
|
Synopsis
|
|
--------
|
|
|
|
.. BEGIN SYNOPSIS
|
|
|
|
.. synopsis::
|
|
|
|
string collect [-a | --allow-empty] [-N | --no-trim-newlines] [STRING ...]
|
|
|
|
.. END SYNOPSIS
|
|
|
|
Description
|
|
-----------
|
|
|
|
.. BEGIN DESCRIPTION
|
|
|
|
``string collect`` collects its input into a single output argument, without splitting the output when used in a command substitution. This is useful when trying to collect multiline output from another command into a variable. Exit status: 0 if any output argument is non-empty, or 1 otherwise.
|
|
|
|
A command like ``echo (cmd | string collect)`` is mostly equivalent to a quoted command substitution (``echo "$(cmd)"``). The main difference is that the former evaluates to zero or one elements whereas the quoted command substitution always evaluates to one element due to string interpolation.
|
|
|
|
If invoked with multiple arguments instead of input, ``string collect`` preserves each argument separately, where the number of output arguments is equal to the number of arguments given to ``string collect``.
|
|
|
|
Any trailing newlines on the input are trimmed, just as with ``"$(cmd)"`` substitution. Use **--no-trim-newlines** to disable this behavior, which may be useful when running a command such as ``set contents (cat filename | string collect -N)``.
|
|
|
|
With **--allow-empty**, ``string collect`` always prints one (empty) argument. This can be used to prevent an argument from disappearing.
|
|
|
|
.. END DESCRIPTION
|
|
|
|
Examples
|
|
--------
|
|
|
|
.. BEGIN EXAMPLES
|
|
|
|
::
|
|
|
|
>_ echo "zero $(echo one\ntwo\nthree) four"
|
|
zero one
|
|
two
|
|
three four
|
|
|
|
>_ echo \"(echo one\ntwo\nthree | string collect)\"
|
|
"one
|
|
two
|
|
three"
|
|
|
|
>_ echo \"(echo one\ntwo\nthree | string collect -N)\"
|
|
"one
|
|
two
|
|
three
|
|
"
|
|
|
|
>_ echo foo(true | string collect --allow-empty)bar
|
|
foobar
|
|
|
|
.. END EXAMPLES
|