/ 
App-CSVUtils-0.030
River stage one • 3 direct dependents • 4 total dependents
/ csv-grep

NAME

csv-grep - Only output row(s) where Perl expression returns true

VERSION

This document describes version 0.030 of csv-grep (from Perl distribution App-CSVUtils), released on 2020-07-30.

SYNOPSIS

Usage:

% csv-grep [-H] [-e=s] [--escape-char=s] [--eval-json=s] [--eval=s]
    [--format=name] [--hash] [--header] [--json] [--(no)naked-res]
    [--no-header] [--no-tsv] [--noheader] [--notsv]
    [--page-result[=program]] [--quote-char=s] [--sep-char=s] [--tsv]
    <filename>

Examples:

Only show rows where the amount field is divisible by 7:

% csv-grep -He '$_->{amount} % 7 ? 1:0' file.csv

Only show rows where date is a Wednesday:

% csv-grep -He 'BEGIN { use DateTime::Format::Natural; $parser = DateTime::Format::Natural->new } $dt = $parser->parse_datetime($_->{date}); $dt->day_of_week == 3' file.csv

DESCRIPTION

This is like Perl's grep performed over rows of CSV. In $_, your Perl code will find the CSV row as an arrayref (or, if you specify -H, as a hashref). $main::row is also set to the row (always as arrayref). $main::rownum contains the row number (2 means the first data row). $main::csv is the Text::CSV_XS object. $main::field_idxs is also available for additional information.

Your code is then free to return true or false based on some criteria. Only rows where Perl expression returns true will be included in the result.

OPTIONS

* marks required options.

Main options

--escape-char=s

Specify character to escape value in field, will be passed to Text::CSV_XS.

Defaults to `\\` (backslash). Overrides `--tsv` option.

--eval-json=s, -e

Perl code (JSON-encoded).

See --eval.

--eval=s*

Perl code.

--filename=s*, -f

Input CSV file.

Use `-` to read from stdin.

--hash, -H

Provide row in $_ as hashref instead of arrayref.

--no-header

By default (`--header`), the first row of the CSV will be assumed to contain field names (and the second row contains the first data row). When you declare that CSV does not have header row (`--no-header`), the first row of the CSV is assumed to contain the first data row. Fields will be named `field1`, `field2`, and so on.

--quote-char=s

Specify field quote character, will be passed to Text::CSV_XS.

Defaults to `"` (double quote). Overrides `--tsv` option.

--sep-char=s

Specify field separator character, will be passed to Text::CSV_XS.

Defaults to `,` (comma). Overrides `--tsv` option.

--tsv

Inform that input file is in TSV (tab-separated) format instead of CSV.

Overriden by `--sep-char`, `--quote-char`, `--escape-char` options. If one of those options is specified, then `--tsv` will be ignored.

Output options

--format=s

Choose output format, e.g. json, text.

Default value:

undef
--json

Set output format to json.

--naked-res

When outputing as JSON, strip result envelope.

Default value:

0

By default, when outputing as JSON, the full enveloped result is returned, e.g.:

[200,"OK",[1,2,3],{"func.extra"=>4}]

The reason is so you can get the status (1st element), status message (2nd element) as well as result metadata/extra result (4th element) instead of just the result (3rd element). However, sometimes you want just the result, e.g. when you want to pipe the result for more post-processing. In this case you can use `--naked-res` so you just get:

[1,2,3]
--page-result

Filter output through a pager.

Other options

--help, -h, -?

Display help message and exit.

--version, -v

Display program's version and exit.

COMPLETION

This script has shell tab completion capability with support for several shells.

bash

To activate bash completion for this script, put:

complete -C csv-grep csv-grep

in your bash startup (e.g. ~/.bashrc). Your next shell session will then recognize tab completion for the command. Or, you can also directly execute the line above in your shell to activate immediately.

It is recommended, however, that you install modules using cpanm-shcompgen which can activate shell completion for scripts immediately.

tcsh

To activate tcsh completion for this script, put:

complete csv-grep 'p/*/`csv-grep`/'

in your tcsh startup (e.g. ~/.tcshrc). Your next shell session will then recognize tab completion for the command. Or, you can also directly execute the line above in your shell to activate immediately.

It is also recommended to install shcompgen (see above).

other shells

For fish and zsh, install shcompgen as described above.

HOMEPAGE

Please visit the project's homepage at https://metacpan.org/release/App-CSVUtils.

SOURCE

Source repository is at https://github.com/perlancar/perl-App-CSVUtils.

BUGS

Please report any bugs or feature requests on the bugtracker website https://rt.cpan.org/Public/Dist/Display.html?Name=App-CSVUtils

When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature.

SEE ALSO

csvgrep.

AUTHOR

perlancar <perlancar@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2020, 2019, 2018, 2017, 2016 by perlancar@cpan.org.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.