NAME

Text::CSV_PP - comma-separated values manipulation routines (PP version)

SYNOPSIS

 use Text::CSV_PP;
 
 $csv = Text::CSV_PP->new();           # create a new object
 # If you want to handle non-ascii char.
 $csv = Text::CSV_PP->new({binary => 1});
 
 $status = $csv->combine(@columns);    # combine columns into a string
 $line   = $csv->string();             # get the combined string
 
 $status  = $csv->parse($line);        # parse a CSV string into fields
 @columns = $csv->fields();            # get the parsed fields
 
 $status = $csv->status();             # get the most recent status
 
 $status = $csv->print($io, $columns); # Write an array of fields immediately
                                       # to a file $io (ex. IO::File object)
 
 $columns = $csv->getline($io);        # Read a line from file $io, parse it
                                       # and return an array ref of fields
 
 $csv->types(\@array);                 # Set column types

DESCRIPTION

Text::CSV_PP has almost same functions of Text::CSV_XS which provides facilities for the composition and decomposition of comma-separated values. As its name suggests, Text::CSV_XS is a XS module and Text::CSV_PP is a Puer Perl one.

METHODS

Almost descriptions are from Text::CSV_XS (0.23 - 0.29)'s pod documentation.

version()

Returns the current module version.

new(\%attr)

Returns a new instance of Text::CSV_PP. The objects attributes are described by the (optional) hash ref \%attr. Currently the following attributes are same as Text::CSV_XS:

quote_char

The char used for quoting fields containing blanks, by default the double quote character ("). A value of undef suppresses quote chars.

eol

An end-of-line string to add to rows, usually undef (nothing, default), "\012" (Line Feed) or "\015\012" (Carriage Return, Line Feed)

escape_char

The char used for escaping certain characters inside quoted fields, by default the same character. (")

sep_char

The char used for separating fields, by default a comme. (,)

allow_whitespace

When this option is set to true, whitespace (TAB's and SPACE's) surrounding the separation character is removed when parsing. So lines like:

  1 , "foo" , bar , 3 , zapp

are now correctly parsed, even though it violates the CSV specs. Note that all whitespace is stripped from start and end of each field. That would make is more a feature than a way to be able to parse bad CSV lines, as

 1,   2.0,  3,   ape  , monkey

will now be parsed as

 ("1", "2.0", "3", "ape", "monkey")

even if the original line was perfectly sane CSV.

allow_loose_quotes

By default, parsing fields that have quote_char characters inside an unquoted field, like

 1,foo "bar" baz,42

would result in a parse error. Though it is still bad practice to allow this format, we cannot help there are some vendors that make their applications spit out lines styled like this.

allow_loose_escapes

By default, parsing fields that have escapee_char characters that escape characters that do not need to be escaped, like:

 my $csv = Text::CSV_PP->new ({ esc_char => "\\" });
 $csv->parse (qq{1,"my bar\'s",baz,42});

would result in a parse error. Though it is still bad practice to allow this format, this option enables you to treat all escape character sequences equal.

binary

If this attribute is TRUE, you may use binary characters in quoted fields, including line feeds, carriage returns and NUL bytes. (The latter must be escaped as "0.) By default this feature is off.

types

A set of column types; this attribute is immediately passed to the types method below. You must not set this attribute otherwise, except for using the types method. For details see the description of the types method below.

always_quote

By default the generated fields are quoted only, if they need to, for example, if they contain the separator. If you set this attribute to a TRUE value, then all fields will be quoted. This is typically easier to handle in external applications.

keep_meta_info

By default, the parsing of input lines is as simple and fast as possible. However, some parsing information - like quotation of the original field - is lost in that process. Set this flag to true to be able to retrieve that information after parsing with the methods meta_info (), is_quoted (), and is_binary () described below. Default is false.

To sum it up,

 $csv = Text::CSV_PP->new();

is equivalent to

 $csv = Text::CSV_PP->new({
     'quote_char'     => '"',
     'escape_char'    => '"',
     'sep_char'       => ',',
     'eol'            => '',
     'always_quote'   => 0,
     'binary'         => 0,
     'keep_meta_info' => 0,
 });

For all of the above mentioned flags, there is an accessor method available where you can inquire for the current value, or change the value

combine

 $status = $csv->combine(@columns);

This object function constructs a CSV string from the arguments, returning success or failure. Upon success, string() can be called to retrieve the resultant CSV string. Upon failure, the value returned by string() is undefined and error_input() can be called to retrieve an invalid argument.

print

 $status = $csv->print($io, $columns);

Similar to combine, but it expects an array ref as input (not an array!) and the resulting string is immediately written to the $io object, typically an IO handle or any other object that offers a print method. Note, this implies that the following is wrong:

 open(FILE, ">whatever");
 $status = $csv->print(\*FILE, $columns);

The glob \*FILE is not an object, thus it doesn't have a print method. The solution is to use an IO::File object or to hide the glob behind an IO::Wrap object. See IO::File(3) and IO::Wrap(3) for details.

string

 $line = $csv->string();

This object function returns the input to parse() or the resultant CSV string of combine(), whichever was called more recently.

parse

 $status = $csv->parse($line);

This object function decomposes a CSV string into fields, returning success or failure. Failure can result from a lack of argument or the given CSV string is improperly formatted. Upon success, fields() can be called to retrieve the decomposed fields . Upon failure, the value returned by fields() is undefined and error_input() can be called to retrieve the invalid argument.

You may use the types() method for setting column types. See the description below.

getline

 $columns = $csv->getline($io);

This is the counterpart to print, like parse is the counterpart to combine: It reads a row from the IO object $io using $io->getline() and parses this row into an array ref. This array ref is returned by the function or undef for failure.

The $csv->string(), $csv->fields() and $csv->status() methods are meaningless, again.

eof

 $eof = $csv->eof ();

If parse () or getline () was used with an IO stream, this mothod will return true (1) if the last call hit end of file, otherwise it will return false (''). This is useful to see the difference between a failure and end of file.

types

 $csv->types(\@tref);

This method is used to force that columns are of a given type. For example, if you have an integer column, two double columns and a string column, then you might do a

 $csv->types([Text::CSV_PP::IV(),
              Text::CSV_PP::NV(),
              Text::CSV_PP::NV(),
              Text::CSV_PP::PV()]);

Column types are used only for decoding columns, in other words by the parse() and getline() methods.

You can unset column types by doing a

 $csv->types(undef);

or fetch the current type settings with

 $types = $csv->types();

fields

 @columns = $csv->fields();

This object function returns the input to combine() or the resultant decomposed fields of parse(), whichever was called more recently.

meta_info

 @flags = $csv->meta_info();

This object function returns the flags of the resultant decomposed fields of parse (), whichever was called more recently.

For each field, a meta_info field will hold flags that tell something about the field returned by the fields () method. The flags are bitwise-or'd like:

0x0001

The field was quoted.

0x0002

The field was binary.

See the is_*** () methods below.

is_quoted

  my $quoted = $csv->is_quoted ($column_idx);

Where $column_idx is the (zero-based) index of the column in the last result of parse ().

This returns a true value if the data in the indicated column was enclosed in quote_char quotes. This might be important for data where ,20070108, is to be treated as a numeric value, and where ,"20070108", is explicitly marked as character string data.

is_binary

  my $binary = $csv->is_binary ($column_idx);

Where $column_idx is the (zero-based) index of the column in the last result of parse ().

This returns a true value if the data in the indicated column contained any byte out of the range [\x09\x20-\x7E]

status

 $status = $csv->status();

This object function returns success (or failure) of combine() or parse(), whichever was called more recently.

error_input

 $bad_argument = $csv->error_input();

This object function returns the erroneous argument (if it exists) of combine() or parse(), whichever was called more recently.

SPEED

Of course Text::CSV_PP is much more slow than CSV_XS. Here is a benchmark test using an example code in Text-CSV_XS-0.29.

 Text::CSV_PP (1.05)
 Benchmark: running combine   1, combine  10, combine 100, parse     1, parse
 10, parse   100 for at least 3 CPU seconds...
 combine   1:  4 wallclock secs ( 3.23 usr +  0.00 sys =  3.23 CPU) @ 12279.22/s (n=39711)
 combine  10:  3 wallclock secs ( 3.16 usr +  0.00 sys =  3.16 CPU) @ 1876.74/s (n=5923)
 combine 100:  3 wallclock secs ( 3.19 usr +  0.00 sys =  3.19 CPU) @ 192.60/s (n=614)
 parse     1:  3 wallclock secs ( 3.25 usr +  0.00 sys =  3.25 CPU) @ 7623.69/s (n=24777)
 parse    10:  3 wallclock secs ( 3.25 usr +  0.00 sys =  3.25 CPU) @ 1334.46/s (n=4337)
 parse   100:  3 wallclock secs ( 3.22 usr +  0.02 sys =  3.24 CPU) @ 132.92/s (n=430)
 Benchmark: timing 50000 iterations of print    io...
 print    io: 32 wallclock secs (30.31 usr +  0.72 sys = 31.03 CPU) @ 1611.24/s (n=50000)
 Benchmark: timing 50000 iterations of getline  io...
 getline  io: 47 wallclock secs (47.33 usr +  0.28 sys = 47.61 CPU) @ 1050.22/s (n=50000)
 File was 46050000 bytes long, line length 920


 Text::CSV_XS (0.29)
 Benchmark: running combine   1, combine  10, combine 100, parse     1, parse
 10, parse   100 for at least 3 CPU seconds...
 combine   1:  3 wallclock secs ( 3.09 usr +  0.00 sys =  3.09 CPU) @ 59718.49/s (n=184769)
 combine  10:  3 wallclock secs ( 3.09 usr +  0.00 sys =  3.09 CPU) @ 26825.09/s (n=82970)
 combine 100:  4 wallclock secs ( 3.16 usr +  0.00 sys =  3.16 CPU) @ 3741.53/s (n=11812)
 parse     1:  3 wallclock secs ( 3.20 usr +  0.00 sys =  3.20 CPU) @ 27434.59/s (n=87873)
 parse    10:  3 wallclock secs ( 3.23 usr +  0.00 sys =  3.23 CPU) @ 4576.38/s (n=14800)
 parse   100:  3 wallclock secs ( 3.19 usr +  0.00 sys =  3.19 CPU) @ 483.53/s (n=1541)
 Benchmark: timing 50000 iterations of print    io...
 print    io:  3 wallclock secs ( 2.11 usr +  0.39 sys =  2.50 CPU) @ 20008.00/s (n=50000)
 Benchmark: timing 50000 iterations of getline  io...
 getline  io: 12 wallclock secs (11.44 usr +  0.19 sys = 11.63 CPU) @ 4300.71/s ( n=50000)
 File was 46050000 bytes long, line length 920

CAVEATS

Below description is entirely from Text::CSV_XS's pod documentation.

This module is based upon a working definition of CSV format which may not be the most general.

1. Allowable characters within a CSV field include 0x09 (tab) and the inclusive range of 0x20 (space) through 0x7E (tilde). In binary mode all characters are accepted, at least in quoted fields:

2. A field within CSV may be surrounded by double-quotes. (The quote char)

3. A field within CSV must be surrounded by double-quotes to contain a comma. (The separator char)

4. A field within CSV must be surrounded by double-quotes to contain an embedded double-quote, represented by a pair of consecutive double-quotes. In binary mode you may additionally use the sequence "0 for representation of a NUL byte.

5. A CSV string may be terminated by 0x0A (line feed) or by 0x0D,0x0A (carriage return, line feed).

AUTHOR

Makamaka Hannyaharamitu, <makamaka[at]cpan.org>

Text::CSV_XS was written by <joe[at]ispsoft.de> and maintained by <h.m.brand[at]xs4all.nl>.

Text::CSV was written by <alan[at]mfgrtl.com>.

COPYRIGHT AND LICENSE

Copyright 2005-2007 by Makamaka Hannyaharamitu, <makamaka[at]cpan.org>

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

SEE ALSO

Text::CSV_XS, Text::CSV

I got many regexp bases from http://www.din.or.jp/~ohzaki/perl.htm