Text::CSV_PP(3) User Contributed Perl Documentation Text::CSV_PP(3)NAMEText::CSV_PP - Text::CSV_XS compatible pure-Perl module
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
$bad_argument = $csv->error_input (); # get the most recent bad argument
$diag = $csv->error_diag (); # if an error occured, explains WHY
$status = $csv->print ($io, $colref); # Write an array of fields
# immediately to a file $io
$colref = $csv->getline ($io); # Read a line from file $io,
# parse it and return an array
# ref of fields
$csv->column_names (@names); # Set column names for getline_hr ()
$ref = $csv->getline_hr ($io); # getline (), but returns a hashref
$eof = $csv->eof (); # Indicate if last parse or
# getline () hit End Of File
$csv->types(\@t_array); # Set column types
DESCRIPTIONText::CSV_PP has almost same functions of Text::CSV_XS which provides
facilities for the composition and decomposition of comma-separated
values. As its name suggests, Text::CSV_XS is a XS module and
Text::CSV_PP is a Puer Perl one.
VERSION
1.29
This module is compatible with Text::CSV_XS 0.80 and later.
Unicode (UTF8)
On parsing (both for "getline ()" and "parse ()"), if the source is
marked being UTF8, then parsing that source will mark all fields that
are marked binary will also be marked UTF8.
On combining ("print ()" and "combine ()"), if any of the combining
fields was marked UTF8, the resulting string will be marked UTF8.
FUNCTIONS
These methods are almost same as Text::CSV_XS. Most of the
documentation was shamelessly copied and replaced from Text::CSV_XS.
See to Text::CSV_XS.
version ()
(Class method) Returns the current backend module version. If you want
the module version, you can use the "VERSION" method,
print Text::CSV->VERSION; # This module version
print Text::CSV->version; # The version of the worker module
# same as Text::CSV->backend->version
new (\%attr)
(Class method) Returns a new instance of Text::CSV_XS. The objects
attributes are described by the (optional) hash ref "\%attr".
Currently the following attributes are available:
eol An end-of-line string to add to rows. "undef" is replaced with an
empty string. The default is "$\". Common values for "eol" are
"\012" (Line Feed) or "\015\012" (Carriage Return, Line Feed).
Cannot be longer than 7 (ASCII) characters.
If both $/ and "eol" equal "\015", parsing lines that end on only a
Carriage Return without Line Feed, will be "parse"d correct. Line
endings, whether in $/ or "eol", other than "undef", "\n", "\r\n",
or "\r" are not (yet) supported for parsing.
sep_char
The char used for separating fields, by default a comma. (",").
Limited to a single-byte character, usually in the range from 0x20
(space) to 0x7e (tilde).
The separation character can not be equal to the quote character.
The separation character can not be equal to the escape character.
See also "CAVEATS" in Text::CSV_XS
allow_whitespace
When this option is set to true, whitespace (TAB's and SPACE's)
surrounding the separation character is removed when parsing. If
either TAB or SPACE is one of the three major characters
"sep_char", "quote_char", or "escape_char" it will not be
considered whitespace.
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 it 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.
blank_is_undef
Under normal circumstances, CSV data makes no distinction between
quoted- and unquoted empty fields. They both end up in an empty
string field once read, so
1,"",," ",2
is read as
("1", "", "", " ", "2")
When writing CSV files with "always_quote" set, the unquoted empty
field is the result of an undefined value. To make it possible to
also make this distinction when reading CSV data, the
"blank_is_undef" option will cause unquoted empty fields to be set
to undef, causing the above to be parsed as
("1", "", undef, " ", "2")
empty_is_undef
Going one step further than "blank_is_undef", this attribute
converts all empty fields to undef, so
1,"",," ",2
is read as
(1, undef, undef, " ", 2)
Note that this only effects fields that are realy empty, not fields
that are empty after stripping allowed whitespace. YMMV.
quote_char
The char used for quoting fields containing blanks, by default the
double quote character ("""). A value of undef suppresses quote
chars. (For simple cases only). Limited to a single-byte
character, usually in the range from 0x20 (space) to 0x7e (tilde).
The quote character can not be equal to the separation character.
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.
In case there is really bad CSV data, like
1,"foo "bar" baz",42
or
1,""foo bar baz"",42
there is a way to get that parsed, and leave the quotes inside the
quoted field as-is. This can be achieved by setting
"allow_loose_quotes" AND making sure that the "escape_char" is not
equal to "quote_char".
escape_char
The character used for escaping certain characters inside quoted
fields. Limited to a single-byte character, usually in the range
from 0x20 (space) to 0x7e (tilde).
The "escape_char" defaults to being the literal double-quote mark
(""") in other words, the same as the default "quote_char". This
means that doubling the quote mark in a field escapes it:
"foo","bar","Escape ""quote mark"" with two ""quote marks""","baz"
If you change the default quote_char without changing the default
escape_char, the escape_char will still be the quote mark. If
instead you want to escape the quote_char by doubling it, you will
need to change the escape_char to be the same as what you changed
the quote_char to.
The escape character can not be equal to the separation character.
allow_loose_escapes
By default, parsing fields that have "escape_char" characters that
escape characters that do not need to be escaped, like:
my $csv = Text::CSV->new ({ escape_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 NULL bytes. (The
latter must be escaped as ""0".) By default this feature is off.
If a string is marked UTF8, binary will be turned on automatically
when binary characters other than CR or NL are encountered. Note
that a simple string like "\x{00a0}" might still be binary, but not
marked UTF8, so setting "{ binary => 1 }" is still a wise option.
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 defined fields will be quoted.
This is typically easier to handle in external applications.
quote_space
By default, a space in a field would trigger quotation. As no rule
exists this to be forced in CSV, nor any for the opposite, the
default is true for safety. You can exclude the space from this
trigger by setting this option to 0.
quote_null
By default, a NULL byte in a field would be escaped. This attribute
enables you to treat the NULL byte as a simple binary character in
binary mode (the "{ binary => 1 }" is set). The default is true.
You can prevent NULL escapes by setting this attribute to 0.
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.
verbatim
This is a quite controversial attribute to set, but it makes hard
things possible.
The basic thought behind this is to tell the parser that the
normally special characters newline (NL) and Carriage Return (CR)
will not be special when this flag is set, and be dealt with as
being ordinary binary characters. This will ease working with data
with embedded newlines.
When "verbatim" is used with "getline ()", "getline ()" auto-
chomp's every line.
Imagine a file format like
M^^Hans^Janssen^Klas 2\n2A^Ja^11-06-2007#\r\n
where, the line ending is a very specific "#\r\n", and the sep_char
is a ^ (caret). None of the fields is quoted, but embedded binary
data is likely to be present. With the specific line ending, that
shouldn't be too hard to detect.
By default, Text::CSV' parse function however is instructed to only
know about "\n" and "\r" to be legal line endings, and so has to
deal with the embedded newline as a real end-of-line, so it can
scan the next line if binary is true, and the newline is inside a
quoted field. With this attribute however, we can tell parse () to
parse the line as if \n is just nothing more than a binary
character.
For parse () this means that the parser has no idea about line
ending anymore, and getline () chomps line endings on reading.
auto_diag
Set to true will cause "error_diag ()" to be automatically be
called in void context upon errors.
If set to a value greater than 1, it will die on errors instead of
warn.
To check future plans and a difference in XS version, please see to
"auto_diag" in Text::CSV_XS.
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,
quote_space => 1,
quote_null => 1,
binary => 0,
keep_meta_info => 0,
allow_loose_quotes => 0,
allow_loose_escapes => 0,
allow_whitespace => 0,
blank_is_undef => 0,
empty_is_undef => 0,
verbatim => 0,
auto_diag => 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
my $quote = $csv->quote_char;
$csv->binary (1);
It is unwise to change these settings halfway through writing CSV data
to a stream. If however, you want to create a new stream using the
available CSV object, there is no harm in changing them.
If the "new ()" constructor call fails, it returns "undef", and makes
the fail reason available through the "error_diag ()" method.
$csv = Text::CSV->new ({ ecs_char => 1 }) or
die "" . Text::CSV->error_diag ();
"error_diag ()" will return a string like
"INI - Unknown attribute 'ecs_char'"
print
$status = $csv->print ($io, $colref);
Similar to "combine () + string () + print", but more efficient. It
expects an array ref as input (not an array!) and the resulting string
is not really created (XS version), but 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 in perl 5.005_xx
and older:
open FILE, ">", "whatever";
$status = $csv->print (\*FILE, $colref);
as in perl 5.005 and older, 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 and
IO::Wrap for details.
For performance reasons the print method doesn't create a result
string. (If its backend is PP version, result strings are created
internally.) In particular the $csv->string (), $csv->status (),
$csv-fields ()> and $csv->error_input () methods are meaningless after
executing this method.
combine
$status = $csv->combine (@columns);
This object function constructs a CSV string from the arguments,
returning success or failure. Failure can result from lack of
arguments or an argument containing an invalid character. 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.
string
$line = $csv->string ();
This object function returns the input to "parse ()" or the resultant
CSV string of "combine ()", whichever was called more recently.
getline
$colref = $csv->getline ($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.
When fields are bound with "bind_columns ()", the return value is a
reference to an empty list.
The $csv->string (), $csv->fields () and $csv->status () methods are
meaningless, again.
getline_all
$arrayref = $csv->getline_all ($io);
$arrayref = $csv->getline_all ($io, $offset);
$arrayref = $csv->getline_all ($io, $offset, $length);
This will return a reference to a list of "getline ($io)" results. In
this call, "keep_meta_info" is disabled. If $offset is negative, as
with "splice ()", only the last "abs ($offset)" records of $io are
taken into consideration.
Given a CSV file with 10 lines:
lines call
----- ---------------------------------------------------------
0..9 $csv->getline_all ($io) # all
0..9 $csv->getline_all ($io, 0) # all
8..9 $csv->getline_all ($io, 8) # start at 8
- $csv->getline_all ($io, 0, 0) # start at 0 first 0 rows
0..4 $csv->getline_all ($io, 0, 5) # start at 0 first 5 rows
4..5 $csv->getline_all ($io, 4, 2) # start at 4 first 2 rows
8..9 $csv->getline_all ($io, -2) # last 2 rows
6..7 $csv->getline_all ($io, -4, 2) # first 2 of last 4 rows
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_hr
The "getline_hr ()" and "column_names ()" methods work together to
allow you to have rows returned as hashrefs. You must call
"column_names ()" first to declare your column names.
$csv->column_names (qw( code name price description ));
$hr = $csv->getline_hr ($io);
print "Price for $hr->{name} is $hr->{price} EUR\n";
"getline_hr ()" will croak if called before "column_names ()".
getline_hr_all
$arrayref = $csv->getline_hr_all ($io);
This will return a reference to a list of "getline_hr ($io)" results.
In this call, "keep_meta_info" is disabled.
column_names
Set the keys that will be used in the "getline_hr ()" calls. If no keys
(column names) are passed, it'll return the current setting.
"column_names ()" accepts a list of scalars (the column names) or a
single array_ref, so you can pass "getline ()"
$csv->column_names ($csv->getline ($io));
"column_names ()" does no checking on duplicates at all, which might
lead to unwanted results. Undefined entries will be replaced with the
string "\cAUNDEF\cA", so
$csv->column_names (undef, "", "name", "name");
$hr = $csv->getline_hr ($io);
Will set "$hr-"{"\cAUNDEF\cA"}> to the 1st field, "$hr-"{""}> to the
2nd field, and "$hr-"{name}> to the 4th field, discarding the 3rd
field.
"column_names ()" croaks on invalid arguments.
bind_columns
Takes a list of references to scalars to store the fields fetched
"getline ()" in. When you don't pass enough references to store the
fetched fields in, "getline ()" will fail. If you pass more than there
are fields to return, the remaining references are left untouched.
$csv->bind_columns (\$code, \$name, \$price, \$description);
while ($csv->getline ($io)) {
print "The price of a $name is \x{20ac} $price\n";
}
eof
$eof = $csv->eof ();
If "parse ()" or "getline ()" was used with an IO stream, this method
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 ();
IV Set field type to integer.
NV Set field type to numeric/float.
PV Set field type to string.
fields
@columns = $csv->fields ();
This object function returns the input to "combine ()" or the resultant
decomposed fields of C successful <parse ()>, whichever was called more
recently.
Note that the return value is undefined after using "getline ()", which
does not fill the data structures returned by "parse ()".
meta_info
@flags = $csv->meta_info ();
This object function returns the flags of the input to "combine ()" or
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 or passed to the
"combine ()" 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 in the range [\x00-\x08,\x10-\x1F,\x7F-\xFF]
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.
error_diag
Text::CSV_PP->error_diag ();
$csv->error_diag ();
$error_code = 0 + $csv->error_diag ();
$error_str = "" . $csv->error_diag ();
($cde, $str, $pos) = $csv->error_diag ();
If (and only if) an error occured, this function returns the
diagnostics of that error.
If called in void context, it will print the internal error code and
the associated error message to STDERR.
If called in list context, it will return the error code and the error
message in that order. If the last error was from parsing, the third
value returned is the best guess at the location within the line that
was being parsed. It's value is 1-based.
Note: $pos does not show the error point in many cases. It is for
conscience's sake.
If called in scalar context, it will return the diagnostics in a single
scalar, a-la $!. It will contain the error code in numeric context, and
the diagnostics message in string context.
To achieve this behavior with CSV_PP, the returned diagnostics is
blessed object.
SetDiag
$csv->SetDiag (0);
Use to reset the diagnostics if you are dealing with errors.
DIAGNOSTICS
If an error occured, $csv->error_diag () can be used to get more
information on the cause of the failure. Note that for speed reasons,
the internal value is never cleared on success, so using the value
returned by error_diag () in normal cases - when no error occured - may
cause unexpected results.
Note: CSV_PP's diagnostics is different from CSV_XS's:
Text::CSV_XS parses csv strings by dividing one character while
Text::CSV_PP by using the regular expressions. That difference makes
the different cause of the failure.
Currently these errors are available:
1001 "sep_char is equal to quote_char or escape_char"
The separation character cannot be equal to either the quotation
character or the escape character, as that will invalidate all
parsing rules.
1002 "INI - allow_whitespace with escape_char or quote_char SP or TAB"
Using "allow_whitespace" when either "escape_char" or "quote_char" is
equal to SPACE or TAB is too ambiguous to allow.
1003 "INI - \r or \n in main attr not allowed"
Using default "eol" characters in either "sep_char", "quote_char", or
"escape_char" is not allowed.
2010 "ECR - QUO char inside quotes followed by CR not part of EOL"
2011 "ECR - Characters after end of quoted field"
2021 "EIQ - NL char inside quotes, binary off"
2022 "EIQ - CR char inside quotes, binary off"
2025 "EIQ - Loose unescaped escape"
2026 "EIQ - Binary character inside quoted field, binary off"
2027 "EIQ - Quoted field not terminated"
2030 "EIF - NL char inside unquoted verbatim, binary off"
2031 "EIF - CR char is first char of field, not part of EOL",
2032 "EIF - CR char inside unquoted, not part of EOL",
2034 "EIF - Loose unescaped quote",
2037 "EIF - Binary character in unquoted field, binary off",
2110 "ECB - Binary character in Combine, binary off"
2200 "EIO - print to IO failed. See errno"
4002 "EIQ - Unescaped ESC in quoted field"
4003 "EIF - ESC CR"
4004 "EUF - "
3001 "EHR - Unsupported syntax for column_names ()"
3002 "EHR - getline_hr () called before column_names ()"
3003 "EHR - bind_columns () and column_names () fields count mismatch"
3004 "EHR - bind_columns () only accepts refs to scalars"
3006 "EHR - bind_columns () did not pass enough refs for parsed fields"
3007 "EHR - bind_columns needs refs to writable scalars"
3008 "EHR - unexpected error in bound fields"
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 2005-2010 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>
perl v5.14.0 2010-12-27 Text::CSV_PP(3)
