NAME
Data::Grid - Incremental read access to grid-based data
VERSION
Version 0.02_01
SYNOPSIS
use Data::Grid;
# Have the parser guess the kind of file, using defaults.
my $grid = Data::Grid->parse('arbitrary.xls');
# or
my $grid = Data::Grid->parse(
source => 'arbitrary.csv', # or xls, or xlsx, or filehandle...
header => 1, # first line is a header everywhere
columns => [qw(a b c)], # override the header
options => \%options, # driver-specific options
);
# Each object contains one or more tables.
for my $table ($grid->tables) {
# Each table has one or more rows.
while (my $row = $table->next) {
# The columns can be dereferenced as an array,
my @cols = @$row; # or just $row->columns
# or, if header is present or fields were named in the
# constructor, as a hash.
my %cols = %$row;
# Now we can do stuff.
}
}
DESCRIPTION
- Problem 1
-
You have a mountain of data files from two decades of using MS Office (and other) products, and you want to collate their contents into someplace sane.
- Problem 2
-
The files are in numerous different formats, and a consistent interface would really cut down on the effort of extracting them.
- Problem 3
-
You've looked at Data::Table and Spreadsheet::Read, but deemed their table-at-a-time strategy to be inappropriate for your purposes.
The goal of Data::Grid is to provide an extensible, uniform, object-oriented interface to all kinds of grid-shaped data. A key behaviour I'm after is to perform an incremental read over a potentially large data source, so as not to unnecessarily gobble up system resources.
DEVELOPER RELEASE
Odds are I will probably decide to change the interface at some point before locking in, and I don't want to guarantee consistency yet. If I do, and you use this, your code will probably break.
Suffice to say this module is ALPHA QUALITY at best.
METHODS
parse $FILE | %PARAMS
The principal way to instantiate a Data::Grid object is through the parse
factory method. You can either pass it a filelike thing or a set of parameters. Filelike thing is either a filename, GLOB
reference, SCALAR
reference or ARRAY
reference of scalars. If the filelike thing is passed alone, its type will be detected using File::MMagic. To tune this behaviour, use the parameters:
- source
-
This is equivalent to
$file
. - header
-
If you know that the document you're opening has a header, set this flag to a true value and it will be consumed for use in "as_hash" in Data::Grid::Row. If there is more than one table in the document, set this value to an
ARRAY
reference of flags. This object will be treated as a ring, meaning that, for instance, if the header designation is[1, 0]
, the third table in the document will be treated as having a header, fourth will not, the fifth will, and so on. - columns
-
Specify a list of columns in lieu of a header, or otherwise override any header, which is thrown away. A single
ARRAY
reference of strings will be duplicated to each table in the document. An array of arrays will be applied to each table with the same wrapping behaviour asheader
. - start
-
Set a row offset, i.e, a number of rows to skip before any header. Since this is an offset, it starts with zero. Same rule applies for multiple tables in the document.
- skip
-
Set a number of rows to skip after the header, defaulting, of course, to zero. Same multi-table rule applies.
- options
-
This
HASH
reference will be passed as-is to the driver. - driver
-
Specify a driver and bypass type detection. Modules under the Data::Grid namespace can be handed in as CSV, Excel, and Excel::XLSX. Prefix with a
+
for other package namespaces. - checker
-
Specify either MMagic or MimeInfo to detect the type of file. MMagic is the default. In lieu of the class name
tables
Generate and return the array of tables.
fh
Retrieve the document's file handle embedded in the grid object.
EXTENSION INTERFACE
Take a look at Data::Grid::CSV or Data::Grid::Excel for clues on how to extend this package.
table_class
Returns the class to use for instantiating tables. Defaults to Data::Grid::Table, which is an abstract class. Override this accessor and its neighbours with your own values for extensions.
row_class
Returns the class to use for instantiating rows. Defaults to Data::Grid::Row.
cell_class
Returns the class to use for instantiating cells. Defaults to Data::Grid::Cell, again an abstract class.
table_params $POSITION
Generate a set of parameters suitable for passing in as a constructor, either as a hash or HASH
reference, depending on calling context.
AUTHOR
Dorian Taylor, <dorian at cpan.org>
BUGS
Please report bugs to GitHub issues.
SUPPORT
You can find documentation for this module with the perldoc command.
perldoc Data::Grid
Alternatively, you can read the documentation on MetaCPAN.
SEE ALSO
COPYRIGHT & LICENSE
Copyright 2010-2018 Dorian Taylor.
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0.
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.