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59 lines
1.8 KiB
ReStructuredText
59 lines
1.8 KiB
ReStructuredText
string-collect - join strings into one
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======================================
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Synopsis
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--------
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.. BEGIN SYNOPSIS
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.. synopsis::
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string collect [-a | --allow-empty] [-N | --no-trim-newlines] [STRING ...]
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.. END SYNOPSIS
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Description
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-----------
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.. BEGIN DESCRIPTION
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``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.
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A command like ``echo (cmd | string collect)`` is mostly equivalent to a quoted command substitution (``echo "$(cmd)"``). The main difference is that the former evaluates to zero or one elements whereas the quoted command substitution always evaluates to one element due to string interpolation.
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If invoked with multiple arguments instead of input, ``string collect`` preserves each argument separately, where the number of output arguments is equal to the number of arguments given to ``string collect``.
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Any trailing newlines on the input are trimmed, just as with ``"$(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)``.
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With **--allow-empty**, ``string collect`` always prints one (empty) argument. This can be used to prevent an argument from disappearing.
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.. END DESCRIPTION
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Examples
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--------
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.. BEGIN EXAMPLES
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::
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>_ echo "zero $(echo one\ntwo\nthree) four"
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zero one
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two
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three four
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>_ echo \"(echo one\ntwo\nthree | string collect)\"
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"one
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two
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three"
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>_ echo \"(echo one\ntwo\nthree | string collect -N)\"
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"one
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two
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three
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"
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>_ echo foo(true | string collect --allow-empty)bar
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foobar
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.. END EXAMPLES
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