Splits the string EXPR into a list of strings and returns that list. By default, empty leading fields are preserved, and empty trailing ones are deleted. (If all fields are empty, they are considered to be trailing.)
In scalar context, returns the number of fields found. In scalar and void
context it splits into the
array. Use of split in scalar and void
context is deprecated, however, because it clobbers your subroutine
If EXPR is omitted, splits the
string. If PATTERN is also omitted,
splits on whitespace (after skipping any leading whitespace). Anything
matching PATTERN is taken to be a delimiter separating the fields. (Note
that the delimiter may be longer than one character.)
If LIMIT is specified and positive, it represents the maximum number
of fields the EXPR will be split into, though the actual number of
fields returned depends on the number of times PATTERN matches within
EXPR. If LIMIT is unspecified or zero, trailing null fields are
stripped (which potential users of
pop would do well to remember).
If LIMIT is negative, it is treated as if an arbitrarily large LIMIT
had been specified. Note that splitting an EXPR that evaluates to the
empty string always returns the empty list, regardless of the LIMIT
A pattern matching the null string (not to be confused with
a null pattern
, which is just one member of the set of patterns
matching a null string) will split the value of EXPR into separate
characters at each point it matches that way. For example:
produces the output 'h:i:t:h:e:r:e'.
As a special case for
split, using the empty pattern
matches only the null string, and is not be confused with the regular use
to mean "the last successful pattern match". So, for
produces the output 'h:i: :t:h:e:r:e'.
Empty leading fields are produced when there are positive-width matches at the beginning of the string; a zero-width match at the beginning of the string does not produce an empty field. For example:
produces the output 'h:i :t:h:e:r:e!'. Empty trailing fields, on the other hand, are produced when there is a match at the end of the string (and when LIMIT is given and is not 0), regardless of the length of the match. For example:
produce the output 'h:i: :t:h:e:r:e:!:' and 'hi:there:', respectively, both with an empty trailing field.
The LIMIT parameter can be used to split a line partially
- ($login, $passwd, $remainder) = split(/:/, $_, 3);
When assigning to a list, if LIMIT is omitted, or zero, Perl supplies a LIMIT one larger than the number of variables in the list, to avoid unnecessary work. For the list above LIMIT would have been 4 by default. In time critical applications it behooves you not to split into more fields than you really need.
If the PATTERN contains parentheses, additional list elements are created from each matching substring in the delimiter.
- split(/([,-])/, "1-10,20", 3);
produces the list value
- (1, '-', 10, ',', 20)
If you had the entire header of a normal Unix email message in $header, you could split it up into fields and their values this way:
- $header =~ s/\n(?=\s)//g; # fix continuation lines
- %hdrs = (UNIX_FROM => split /^(\S*?):\s*/m, $header);
may be replaced with an expression to specify
patterns that vary at runtime. (To do runtime compilation only once,
As a special case, specifying a PATTERN of space (
) will split on
white space just as
split with no arguments does. Thus,
be used to emulate awk's default behavior, whereas
will give you as many null initial fields as there are leading spaces.
is like a
except that any leading
whitespace produces a null first field. A
split with no arguments
really does a
split(' ', $_)
A PATTERN of
is treated as if it were
, since it isn't
much use otherwise.
- @fields = split /(A)|B/, "1A2B3";
- # @fields is (1, 'A', 2, undef, 3)