try_or_stop_print_pattern

Try to run a capture function. If it fails we wrap the error
message with a more informative message that also includes the
generated pattern.

User-friendly functions for extracting a data
table (row for each match, column for each group)
from non-tabular text data using regular expressions,
and for melting columns that match a regular expression.
Patterns are defined using a readable syntax
that makes it easy to build complex patterns
in terms of simpler, re-usable sub-patterns.
Named R arguments are translated to column names
in the output; capture groups without names are used
internally in order to provide a standard interface
to three regular expression 'C' libraries
('PCRE', 'RE2', 'ICU').
Output can also include numeric columns via
user-specified type conversion functions.

Toby Hocking

Named Capture to Data Tables

try_or_stop_print_pattern function

<dl> <dt>expr</dt>
<dd>expression to try.</dd> <dt>pat</dt>
<dd>regex pattern string.</dd> <dt>engine</dt>
<dd>string: regex <code>engine</code>.</dd></dl>

Arguments

Toby Hocking &lt;toby.hocking@r-project.org&gt; [aut, cre]

Author

try or stop print pattern — try_or_stop_print_pattern

<dl>

 <dt>expr</dt>
<dd>expression to try.</dd>

 <dt>pat</dt>
<dd>regex pattern string.</dd>

 <dt>engine</dt>
<dd>string: regex <code>engine</code>.</dd>

</dl>

try_or_stop_print_pattern: try or stop print pattern

Description

Usage

Arguments

Author