NAME
    String::Format - sprintf-like string formatting capabilities with
    arbitrary format definitions

ABSTRACT
    String::Format allows for sprintf-style formatting capabilities with
    arbitrary format definitions

SYNOPSIS
      use String::Format;

      my %fruit = (
            'a' => "apples",
            'b' => "bannanas",
            'g' => "grapefruits",
            'm' => "melons",
            'w' => "watermelons",
      );

      my $format = "I like %a, %b, and %g, but not %m or %w.";

      print stringf($format, %fruit);
  
      # prints:
      # I like apples, bannanas, and grapefruits, but not melons or watermelons.

DESCRIPTION
    String::Format lets you define arbitrary printf-like format sequences to
    be expanded. This module would be most useful in configuration files and
    reporting tools, where the results of a query need to be formatted in a
    particular way. It was inspired by mutt's index_format and related
    directives (see
    <URL:http://www.mutt.org/doc/manual/manual-6.html#index_format>).

FUNCTIONS
  stringf
    String::Format exports a single function called stringf. stringf takes
    two arguments: a format string (see FORMAT STRINGS, below) and a
    reference to a hash of name => value pairs. These name => value pairs
    are what will be expanded in the format string.

FORMAT STRINGS
    Format strings must match the following regular expression:

      qr/
         (%             # leading '%'
          (-)?          # left-align, rather than right
          (\d*)?        # (optional) minimum field width
          (?:\.(\d*))?  # (optional) maximum field width
          ({.*?})?      # (optional) stuff inside
          (\S)          # actual format character
         )/x;

    If the escape character specified does not exist in %args, then the
    original string is used. The alignment, minimum width, and maximum width
    options function identically to how they are defined in sprintf(3) (any
    variation is a bug, and should be reported).

    Note that Perl's sprintf definition is a little more liberal than the
    above regex; the deviations were intentional, and all deal with numeric
    formatting (the #, 0, and + leaders were specifically left out).

    The value attached to the key can be a scalar value or a subroutine
    reference; if it is a subroutine reference, then anything between the
    '{' and '}' ($5 in the above regex) will be passed as $_[0] to the
    subroutine reference. This allows for entries such as this:

      %args = (
          d => sub { POSIX::strftime($_[0], localtime) }, 
      );

    Which can be invoked with this format string:

      "It is %{%M:%S}d right now, on %{%A, %B %e}d."

    And result in (for example):

      It is 17:45 right now, on Monday, February 4.

    Note that since the string is passed unmolested to the subroutine
    reference, and strftime would Do The Right Thing with this data, the
    above format string could be written as:

      "It is %{%M:%S right now, on %A, %B %e}d."

    By default, the formats 'n', 't', and '%' are defined to be a newline,
    tab, and '%', respectively, if they are not already defined in the
    hashref of arguments that gets passed it. So we can add carriage returns
    simply:

      "It is %{%M:%S right now, on %A, %B %e}d.%n"

    Because of how the string is parsed, the normal "\n" and "\t" are turned
    into two characters each, and are not treated as a newline and tab. This
    is a bug.

FACTORY METHOD
    String::Format also supports a class method, named stringfactory, which
    will return reference to a "primed" subroutine. stringfatory should be
    passed a reference to a hash of value; the returned subroutine will use
    these values as the %args hash.

      my $self = Some::Groovy::Package->new($$, $<, $^T);
      my %formats = (
            'i' => sub { $self->id      },
            'd' => sub { $self->date    },
            's' => sub { $self->subject },
            'b' => sub { $self->body    },
      );
      my $index_format = String::Format->stringfactory(\%formats);

      print $index_format->($format1);
      print $index_format->($format2);

    This subroutine reference can be assigned to a local symbol table entry,
    and called normally, of course:

      *reformat = String::Format->stringfactory(\%formats);

      my $reformed = reformat($format_string);

LICENSE
    "String::Format" is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by the
    Free Software Foundation; version 2.

AUTHOR
    darren chamberlain <darren@cpan.org>

