1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359
|
use strict;
use warnings;
package String::Formatter::Cookbook 1.235;
# ABSTRACT: ways to put String::Formatter to use
1;
#pod =encoding utf-8
#pod
#pod =head1 OVERVIEW
#pod
#pod String::Formatter is a pretty simple system for building formatting routines,
#pod but it can be hard to get started without an idea of the sort of things that
#pod are possible.
#pod
#pod =head1 BASIC RECIPES
#pod
#pod =head2 constants only
#pod
#pod The simplest stringf interface you can provide is one that just formats
#pod constant strings, allowing the user to put them inside other fixed strings with
#pod alignment:
#pod
#pod use String::Formatter stringf => {
#pod input_processor => 'forbid_input',
#pod codes => {
#pod a => 'apples',
#pod b => 'bananas',
#pod w => 'watermelon',
#pod },
#pod };
#pod
#pod print stringf('I eat %a and %b but never %w.');
#pod
#pod # Output:
#pod # I eat apples and bananas but never watermelon.
#pod
#pod If the user tries to parameterize the string by passing arguments after the
#pod format string, an exception will be raised.
#pod
#pod =head2 sprintf-like conversions
#pod
#pod Another common pattern is to create a routine that behaves like Perl's
#pod C<sprintf>, but with a different set of conversion routines. (It will also
#pod almost certainly have much simpler semantics than Perl's wildly complex
#pod behavior.)
#pod
#pod use String::Formatter stringf => {
#pod codes => {
#pod s => sub { $_ }, # string itself
#pod l => sub { length }, # length of input string
#pod e => sub { /[^\x00-\x7F]/ ? '8bit' : '7bit' }, # ascii-safeness
#pod },
#pod };
#pod
#pod print stringf(
#pod "My name is %s. I am about %l feet tall. I use an %e alphabet.\n",
#pod 'Ricardo',
#pod 'ffffff',
#pod 'abcchdefghijklllmnñopqrrrstuvwxyz',
#pod );
#pod
#pod # Output:
#pod # My name is Ricardo. I am about 6 feet tall. I use an 8bit alphabet.
#pod
#pod B<Warning>: The behavior of positional string replacement when the conversion
#pod codes mix constant strings and code references is currently poorly nailed-down.
#pod Do not rely on it yet.
#pod
#pod =head2 named conversions
#pod
#pod This recipe acts a bit like Python's format operator when given a dictionary.
#pod Rather than matching format code position with input ordering, inputs can be
#pod chosen by name.
#pod
#pod use String::Formatter stringf => {
#pod input_processor => 'require_named_input',
#pod string_replacer => 'named_replace',
#pod
#pod codes => {
#pod s => sub { $_ }, # string itself
#pod l => sub { length }, # length of input string
#pod e => sub { /[^\x00-\x7F]/ ? '8bit' : '7bit' }, # ascii-safeness
#pod },
#pod };
#pod
#pod print stringf(
#pod "My %{which}s name is %{name}s. My name is %{name}l letters long.",
#pod {
#pod which => 'first',
#pod name => 'Marvin',
#pod },
#pod );
#pod
#pod # Output:
#pod # My first name is Marvin. My name is 6 letters long.
#pod
#pod Because this is a useful recipe, there is a shorthand for it:
#pod
#pod use String::Formatter named_stringf => {
#pod codes => {
#pod s => sub { $_ }, # string itself
#pod l => sub { length }, # length of input string
#pod e => sub { /[^\x00-\x7F]/ ? '8bit' : '7bit' }, # ascii-safeness
#pod },
#pod };
#pod
#pod =head2 method calls
#pod
#pod Some objects provide methods to stringify them flexibly. For example, many
#pod objects that represent timestamps allow you to call C<strftime> or something
#pod similar. The C<method_replace> string replacer comes in handy here:
#pod
#pod use String::Formatter stringf => {
#pod input_processor => 'require_single_input',
#pod string_replacer => 'method_replace',
#pod
#pod codes => {
#pod f => 'strftime',
#pod c => 'format_cldr',
#pod s => sub { "$_[0]" },
#pod },
#pod };
#pod
#pod print stringf(
#pod "%{%Y-%m-%d}f is also %{yyyy-MM-dd}c. Default string is %s.",
#pod DateTime->now,
#pod );
#pod
#pod # Output:
#pod # 2009-11-17 is also 2009-11-17. Default string is 2009-11-17T15:35:11.
#pod
#pod This recipe is available as the export C<method_stringf>:
#pod
#pod use String::Formatter method_stringf => {
#pod codes => {
#pod f => 'strftime',
#pod c => 'format_cldr',
#pod s => sub { "$_[0]" },
#pod },
#pod };
#pod
#pod You can easily use this to implement an actual stringf-like method:
#pod
#pod package MyClass;
#pod
#pod use String::Formatter method_stringf => {
#pod -as => '_stringf',
#pod codes => {
#pod f => 'strftime',
#pod c => 'format_cldr',
#pod s => sub { "$_[0]" },
#pod },
#pod };
#pod
#pod sub format {
#pod my ($self, $format) = @_;
#pod return _stringf($format, $self);
#pod }
#pod
#pod =cut
__END__
=pod
=encoding utf-8
=head1 NAME
String::Formatter::Cookbook - ways to put String::Formatter to use
=head1 VERSION
version 1.235
=head1 OVERVIEW
String::Formatter is a pretty simple system for building formatting routines,
but it can be hard to get started without an idea of the sort of things that
are possible.
=head1 PERL VERSION
This library should run on perls released even a long time ago. It should work
on any version of perl released in the last five years.
Although it may work on older versions of perl, no guarantee is made that the
minimum required version will not be increased. The version may be increased
for any reason, and there is no promise that patches will be accepted to lower
the minimum required perl.
=head1 BASIC RECIPES
=head2 constants only
The simplest stringf interface you can provide is one that just formats
constant strings, allowing the user to put them inside other fixed strings with
alignment:
use String::Formatter stringf => {
input_processor => 'forbid_input',
codes => {
a => 'apples',
b => 'bananas',
w => 'watermelon',
},
};
print stringf('I eat %a and %b but never %w.');
# Output:
# I eat apples and bananas but never watermelon.
If the user tries to parameterize the string by passing arguments after the
format string, an exception will be raised.
=head2 sprintf-like conversions
Another common pattern is to create a routine that behaves like Perl's
C<sprintf>, but with a different set of conversion routines. (It will also
almost certainly have much simpler semantics than Perl's wildly complex
behavior.)
use String::Formatter stringf => {
codes => {
s => sub { $_ }, # string itself
l => sub { length }, # length of input string
e => sub { /[^\x00-\x7F]/ ? '8bit' : '7bit' }, # ascii-safeness
},
};
print stringf(
"My name is %s. I am about %l feet tall. I use an %e alphabet.\n",
'Ricardo',
'ffffff',
'abcchdefghijklllmnñopqrrrstuvwxyz',
);
# Output:
# My name is Ricardo. I am about 6 feet tall. I use an 8bit alphabet.
B<Warning>: The behavior of positional string replacement when the conversion
codes mix constant strings and code references is currently poorly nailed-down.
Do not rely on it yet.
=head2 named conversions
This recipe acts a bit like Python's format operator when given a dictionary.
Rather than matching format code position with input ordering, inputs can be
chosen by name.
use String::Formatter stringf => {
input_processor => 'require_named_input',
string_replacer => 'named_replace',
codes => {
s => sub { $_ }, # string itself
l => sub { length }, # length of input string
e => sub { /[^\x00-\x7F]/ ? '8bit' : '7bit' }, # ascii-safeness
},
};
print stringf(
"My %{which}s name is %{name}s. My name is %{name}l letters long.",
{
which => 'first',
name => 'Marvin',
},
);
# Output:
# My first name is Marvin. My name is 6 letters long.
Because this is a useful recipe, there is a shorthand for it:
use String::Formatter named_stringf => {
codes => {
s => sub { $_ }, # string itself
l => sub { length }, # length of input string
e => sub { /[^\x00-\x7F]/ ? '8bit' : '7bit' }, # ascii-safeness
},
};
=head2 method calls
Some objects provide methods to stringify them flexibly. For example, many
objects that represent timestamps allow you to call C<strftime> or something
similar. The C<method_replace> string replacer comes in handy here:
use String::Formatter stringf => {
input_processor => 'require_single_input',
string_replacer => 'method_replace',
codes => {
f => 'strftime',
c => 'format_cldr',
s => sub { "$_[0]" },
},
};
print stringf(
"%{%Y-%m-%d}f is also %{yyyy-MM-dd}c. Default string is %s.",
DateTime->now,
);
# Output:
# 2009-11-17 is also 2009-11-17. Default string is 2009-11-17T15:35:11.
This recipe is available as the export C<method_stringf>:
use String::Formatter method_stringf => {
codes => {
f => 'strftime',
c => 'format_cldr',
s => sub { "$_[0]" },
},
};
You can easily use this to implement an actual stringf-like method:
package MyClass;
use String::Formatter method_stringf => {
-as => '_stringf',
codes => {
f => 'strftime',
c => 'format_cldr',
s => sub { "$_[0]" },
},
};
sub format {
my ($self, $format) = @_;
return _stringf($format, $self);
}
=head1 AUTHORS
=over 4
=item *
Ricardo Signes <cpan@semiotic.systems>
=item *
Darren Chamberlain <darren@cpan.org>
=back
=head1 COPYRIGHT AND LICENSE
This software is Copyright (c) 2022 by Ricardo Signes <cpan@semiotic.systems>.
This is free software, licensed under:
The GNU General Public License, Version 2, June 1991
=cut
|