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NAME ==== String::Fields - class for setting fixed size fields in a Str SYNOPSIS ======== ```perl6 use String::Fields; my $sf := String::Fields.new(2,3,4) .say for $sf.set-string("abcdefghijklmnopqrstuvwxyz"); # ab # cde # fghi my $sf := String::Fields.new(2 => 5, 8, 3); my $s = "012345678901234567890"; $s.&apply-fields($sf); # or: apply-fields($s,$sf) say $s; # 012345678901234567890 say $s; # 23456 say $s; # 78901234 say $s; # 567 say $s.join(":"); # 23456:78901234:567 # one time application $s.&apply-fields(2,3,4); # or: apply-fields($s,2,3,4) # using a literal string my @fields = "abcdefg".&apply-fields(2,3); # ["ab","cde"] ``` DESCRIPTION =========== String::Fields allows one to specify fixed length fields that can be applied to a string, effectively turning it into a sequence of strings that can be individually accessed or iterated over. When the object is loaded with a string, it can be used as a string in all the normal ways that a string would. METHODS ======= new --- my $sf := String::Fields.new(2,3,4) The `new` method creates a new `String::Fields` object that contains the format information of the fields. It takes any number of arguments to indicate the position and width of the fields. If the argument consists of just a number, it means the width of a field from where the last field has ended (or from position 0 for the first argument). If the argument consists of a `Pair`, then the key is taken for the offset, and the value is taken to be the width. Please note that this **just** sets the format information. This allows the same object to be used for different strings. Setting the string to be used, is either done with the `set-string` method, or by calling the `apply-fields` subroutine. join ---- $s.join(":") Joins all fields together with the given separator. set-string ---------- $sf.set-string($string) The `set-string` method sets the string to which the format information should be applied. SUBROUTINES =========== apply-fields ------------ apply-fields($s,$sf); # or $s.&apply-fields($sf) # one time application $s.&apply-fields(2,3,4); # or: apply-fields($s,2,3,4) # using a literal string my @fields = "abcdefg".&apply-fields(2,3); # ["ab","cde"] If the first argument to the `apply-fields` subroutine is a variable with a string in it, then it will become a `String::Fields` object (but will still act as the original string). If it is a string literal, then the created / applied `String::Fields` object will be returned. The other arguments indicate the fields that should be applie. This can be either be a `String::Fields` object, or it can any number of field specifications, as can be passed to the `new` method. AUTHOR ====== Elizabeth Mattijsen <[email protected]> Source can be located at: https://github.com/lizmat/String-Fields . Comments and Pull Requests are welcome. COPYRIGHT AND LICENSE ===================== Copyright 2020 Elizabeth Mattijsen This library is free software; you can redistribute it and/or modify it under the Artistic License 2.0.