NAME¶
Lintian::Data - Lintian interface to query lists of keywords
SYNOPSIS¶
my $keyword;
my $list = Lintian::Data->new('type');
if ($list->known($keyword)) {
# do something ...
}
my $hash = Lintian::Data->new('another-type', qr{\s++});
if ($list->value($keyword) > 1) {
# do something ...
}
my @keywords = $list->all;
DESCRIPTION¶
Lintian::Data provides a way of loading a list of keywords or key/value pairs
from a file in the Lintian root and then querying that list. The lists are
stored in the
data directory of the Lintian root and consist of one
keyword or key/value pair per line. Blank lines and lines beginning with
"#" are ignored. Leading and trailing whitespace is stripped.
If requested, the lines are split into key/value pairs with a given separator
regular expression. Otherwise, keywords are taken verbatim as they are listed
in the file and may include spaces.
This module allows lists such as menu sections, doc-base sections, obsolete
packages, package fields, and so forth to be stored in simple, easily editable
files.
NB: By default Lintian::Data is lazy and defers loading of the data file until
it is actually needed.
Interface for the CODE argument¶
This section describes the interface between for the CODE argument for the class
method new.
The sub will be called once for each key/pair with three arguments, KEY, VALUE
and CURVALUE. The first two are the key/value pair parsed from the data file
and CURVALUE is current value associated with the key. CURVALUE will be
"undef" the first time the sub is called with that KEY argument.
The sub can then modify VALUE in some way and return the new value for that KEY.
If CURVALUE is not "undef", the sub may return "undef" to
indicate that the current value should still be used. It is not permissible
for the sub to return "undef" if CURVALUE is "undef".
Where Perl semantics allow it, the sub can modify CURVALUE and the changes will
be reflected in the result. As an example, if CURVALUE is a hashref, new keys
can be inserted etc.
CLASS METHODS¶
- new(TYPE [,SEPARATOR[, CODE]])
- Creates a new Lintian::Data object for the given TYPE. TYPE is a partial
path relative to the data directory and should correspond to a file
in that directory. The contents of that file will be loaded into memory
and returned as part of the newly created object. On error, new()
throws an exception.
If SEPARATOR is given, it will be used as a regular expression for splitting
the lines into key/value pairs.
If CODE is also given, it is assumed to be a sub that will pre-process the
key/value pairs. See the "Interface for the CODE argument"
above.
A given file will only be loaded once. If new() is called again with
the same TYPE argument, the data previously loaded will be reused,
avoiding multiple file reads.
- set_vendor(PROFILE)
- Specifies vendor profile. It must be set before the first data file is
loaded.
INSTANCE METHODS¶
- all()
- Returns all keywords listed in the data file as a list (in no particular
order; the original order is not preserved). In a scalar context, returns
the number of keywords.
- known(KEYWORD)
- Returns true if KEYWORD was listed in the data file represented by this
Lintian::Data instance and false otherwise.
- value(KEYWORD)
- Returns the value attached to KEYWORD if it was listed in the data file
represented by this Lintian::Data instance and the undefined value
otherwise. If SEPARATOR was not given, the value will '1'.
DIAGNOSTICS¶
- no data type specified
- new() was called without a TYPE argument.
- unknown data type %s
- The TYPE argument to new() did not correspond to a file in the
data directory of the Lintian root.
- undefined value for %s (type: %s)
- The CODE argument return undef for the KEY and no previous value for that
KEY was available.
FILES¶
- LINTIAN_INCLUDE_DIR/data
- The files loaded by this module must be located in this directory.
Relative paths containing a "/" are permitted, so files may be
organized in subdirectories in this directory.
Note that lintian supports multiple LINTIAN_INCLUDE_DIRs.
AUTHOR¶
Originally written by Russ Allbery <rra@debian.org> for Lintian.
SEE ALSO¶
lintian(1),
<
https://lintian.debian.org/manual/section-2.6.html>