yuezonghe | 824eb0c | 2024-06-27 02:32:26 -0700 | [diff] [blame] | 1 | |
| 2 | Text::Template v1.46 |
| 3 | |
| 4 | This is a library for generating form letters, building HTML pages, or |
| 5 | filling in templates generally. A `template' is a piece of text that |
| 6 | has little Perl programs embedded in it here and there. When you |
| 7 | `fill in' a template, you evaluate the little programs and replace |
| 8 | them with their values. |
| 9 | |
| 10 | Here's an example of a template: |
| 11 | |
| 12 | Dear {$title} {$lastname}, |
| 13 | |
| 14 | It has come to our attention that you are delinquent in your |
| 15 | {$monthname[$last_paid_month]} payment. Please remit |
| 16 | ${sprintf("%.2f", $amount)} immediately, or your patellae may |
| 17 | be needlessly endangered. |
| 18 | |
| 19 | Love, |
| 20 | |
| 21 | Mark "{nickname(rand 20)}" Dominus |
| 22 | |
| 23 | |
| 24 | The result of filling in this template is a string, which might look |
| 25 | something like this: |
| 26 | |
| 27 | Dear Mr. Gates, |
| 28 | |
| 29 | It has come to our attention that you are delinquent in your |
| 30 | February payment. Please remit |
| 31 | $392.12 immediately, or your patellae may |
| 32 | be needlessly endangered. |
| 33 | |
| 34 | |
| 35 | Love, |
| 36 | |
| 37 | Mark "Vizopteryx" Dominus |
| 38 | |
| 39 | You can store a template in a file outside your program. People can |
| 40 | modify the template without modifying the program. You can separate |
| 41 | the formatting details from the main code, and put the formatting |
| 42 | parts of the program into the template. That prevents code bloat and |
| 43 | encourages functional separation. |
| 44 | |
| 45 | You can fill in the template in a `Safe' compartment. This means that |
| 46 | if you don't trust the person who wrote the code in the template, you |
| 47 | won't have to worry that they are tampering with your program when you |
| 48 | execute it. |
| 49 | |
| 50 | ---------------------------------------------------------------- |
| 51 | |
| 52 | Text::Template was originally released some time in late 1995 or early |
| 53 | 1996. After three years of study and investigation, I rewrote it from |
| 54 | scratch in January 1999. The new version, 1.0, was much faster, |
| 55 | delivered better functionality and was almost 100% backward-compatible |
| 56 | with the previous beta versions. |
| 57 | |
| 58 | I have added a number of useful features and conveniences since the |
| 59 | 1.0 release, while still retaining backward compatibility. With one |
| 60 | merely cosmetic change, the current version of Text::Template passes |
| 61 | the test suite that the old beta versions passed. |
| 62 | |
| 63 | Questions or comments should be addressed to |
| 64 | mjd-perl-template+@plover.com. This address goes directly to me, and |
| 65 | not to anyone else; it is not a mailing list address. |
| 66 | |
| 67 | To receive occasional announcements of new versions of T::T, send an |
| 68 | empty note to mjd-perl-template-request@plover.com. This mailing list |
| 69 | is not for discussion; it is for announcements only. Therefore, there |
| 70 | is no address for sending messages to the list. |
| 71 | |
| 72 | You can get the most recent version of Text::Template, news, comments, |
| 73 | and other collateral information from |
| 74 | <URL:http://www.plover.com/~mjd/perl/Template/>. |
| 75 | |
| 76 | ---------------------------------------------------------------- |
| 77 | |
| 78 | What's new in v1.46 since v1.44: |
| 79 | |
| 80 | Thanks to Rik Signes, there is a new |
| 81 | Text::Template->append_text_to_output method, which |
| 82 | Text::Template always uses whenever it wants to emit output. |
| 83 | You can subclass this to get control over the output, for |
| 84 | example for postprocessing. |
| 85 | |
| 86 | A spurious warning is no longer emitted when the TYPE |
| 87 | parameter to ->new is omitted. |
| 88 | |
| 89 | ---------------------------------------------------------------- |
| 90 | What's new in v1.44 since v1.43: |
| 91 | |
| 92 | This is a maintentance release. There are no feature changes. |
| 93 | |
| 94 | _scrubpkg, which was responsible for eptying out temporary |
| 95 | packages after the module had done with them, wasn't always |
| 96 | working; the result was memory-leaks in long-running |
| 97 | applications. This should be fixed now, and there is a test |
| 98 | in the test suite for it. |
| 99 | |
| 100 | Minor changes to the test suite to prevent spurious errors. |
| 101 | |
| 102 | Minor documentation changes. |
| 103 | |
| 104 | ---------------------------------------------------------------- |
| 105 | What's new in v1.43 since v1.42: |
| 106 | |
| 107 | The ->new method now fails immediately and sets |
| 108 | $Text::Template::ERROR if the file that is named by a filename |
| 109 | argument does not exist or cannot be opened for some other |
| 110 | reason. Formerly, the constructor would succeed and the |
| 111 | ->fill_in call would fail. |
| 112 | |
| 113 | ---------------------------------------------------------------- |
| 114 | |
| 115 | What's new in v1.42 since v1.41: |
| 116 | |
| 117 | This is a maintentance release. There are no feature changes. |
| 118 | |
| 119 | Fixed a bug relating to use of UNTAINT under perl 5.005_03 and |
| 120 | possibly other versions. |
| 121 | |
| 122 | Taint-related tests are now more comprehensive. |
| 123 | ---------------------------------------------------------------- |
| 124 | |
| 125 | What's new in v1.41 since v1.40: |
| 126 | |
| 127 | This is a maintentance release. There are no feature changes. |
| 128 | |
| 129 | Tests now work correctly on Windows systems and possibly on |
| 130 | other non-unix systems. |
| 131 | |
| 132 | ---------------------------------------------------------------- |
| 133 | |
| 134 | What's new in v1.40 since v1.31: |
| 135 | |
| 136 | New UNTAINT option tells the module that it is safe to 'eval' |
| 137 | code even though it has come from a file or filehandle. |
| 138 | |
| 139 | Code added to prevent memory leaks when filling many |
| 140 | templates. Thanks to Itamar Almeida de Carvalho. |
| 141 | |
| 142 | Bug fix: $OUT was not correctly initialized when used in |
| 143 | conjunction with SAFE. |
| 144 | |
| 145 | You may now use a glob ref when passing a filehandle to the |
| 146 | ->new funcion. Formerly, a glob was reuqired. |
| 147 | |
| 148 | New subclass: Text::Template::Preprocess. Just like |
| 149 | Text::Template, but you may supply a PREPROCESS option in the |
| 150 | constructor or the fill_in call; this is a function which |
| 151 | receives each code fragment prior to evaluation, and which may |
| 152 | modify and return the fragment; the modified fragment is what |
| 153 | is evaluated. |
| 154 | |
| 155 | Error messages passed to BROKEN subroutines will now report |
| 156 | the correct line number of the template at which the error |
| 157 | occurred: |
| 158 | |
| 159 | Illegal division by zero at template line 37. |
| 160 | |
| 161 | If the template comes from a file, the filename will be |
| 162 | reported as well: |
| 163 | |
| 164 | Illegal division by zero at catalog.tmpl line 37. |
| 165 | |
| 166 | |
| 167 | INCOMPATIBLE CHANGE: |
| 168 | |
| 169 | The format of the default error message has changed. It used |
| 170 | to look like: |
| 171 | |
| 172 | Program fragment at line 30 delivered error ``Illegal division by zero'' |
| 173 | |
| 174 | It now looks like: |
| 175 | |
| 176 | Program fragment delivered error ``Illegal division by zero at catalog.tmpl line 37'' |
| 177 | |
| 178 | Note that the default message used to report the line number |
| 179 | at which the program fragment began; it now reports the line |
| 180 | number at which the error actually occurred. |
| 181 | |
| 182 | ---------------------------------------------------------------- |
| 183 | What's new in v1.31 since v1.23: |
| 184 | |
| 185 | Just bug fixes---fill_in_string was failing. Thanks to |
| 186 | Donald L. Greer Jr. for the test case. |
| 187 | |
| 188 | ---------------------------------------------------------------- |
| 189 | What's new in v1.23 since v1.22: |
| 190 | |
| 191 | Small bug fix: DELIMITER and other arguments were being |
| 192 | ignored in calls to fill_in_file and fill_this_in. (Thanks to |
| 193 | Jonathan Roy for reporting this.) |
| 194 | |
| 195 | ---------------------------------------------------------------- |
| 196 | What's new in v1.22 since v1.20: |
| 197 | |
| 198 | You can now specify that certain Perl statements be prepended |
| 199 | to the beginning of every program fragment in a template, |
| 200 | either per template, or for all templates, or for the duration |
| 201 | of only one call to fill_in. This is useful, for example, if |
| 202 | you want to enable `strict' checks in your templates but you |
| 203 | don't want to manually add `use strict' to the front of every |
| 204 | program fragment everywhere. |
| 205 | |
| 206 | ---------------------------------------------------------------- |
| 207 | What's new in v1.20 since v1.12: |
| 208 | |
| 209 | You can now specify that the program fragment delimiters are |
| 210 | strings other than { and }. This has three interesting |
| 211 | effects: First, it changes the delimiter strings. Second, it |
| 212 | disables the special meaning of \, so you have to be really, |
| 213 | really sure that the delimiters will not appear in your |
| 214 | templates. And third, because of the simplifications |
| 215 | introduced by the elimination of \ processing, template |
| 216 | parsing is 20-25% faster. |
| 217 | |
| 218 | See the manual section on `Alternative Delimiters'. |
| 219 | |
| 220 | Fixed bug having to do with undefined values in HASH options. |
| 221 | In particular, Text::Template no longer generates a warning if |
| 222 | you try to give a variable an undefined value. |
| 223 | |
| 224 | ---------------------------------------------------------------- |
| 225 | |
| 226 | What's new in v1.12 since v1.11: |
| 227 | |
| 228 | I forgot to say that Text::Template ISA Exporter, so the |
| 229 | exported functions never got exported. Duhhh! |
| 230 | |
| 231 | Template TYPEs are now case-insensitive. The `new' method now |
| 232 | diagnoses attempts to use an invalid TYPE. |
| 233 | |
| 234 | More tests for these things. |
| 235 | |
| 236 | ---------------------------------------------------------------- |
| 237 | |
| 238 | What's new in v1.11 since v1.10: |
| 239 | |
| 240 | Fixed a bug in the way backslashes were processed. The 1.10 |
| 241 | behavior was incompatible with the beta versions and was also |
| 242 | inconvenient. (`\n' in templates was replaced with `n' before |
| 243 | it was given to Perl for evaluation.) The new behavior is |
| 244 | also incompatible with the beta versions, but it is only a |
| 245 | little bit incompatible, and it is probbaly better. |
| 246 | |
| 247 | Documentation for the new behavior, and tests for the bug. |
| 248 | |
| 249 | ---------------------------------------------------------------- |
| 250 | |
| 251 | What's new in v1.10 since v1.03: |
| 252 | |
| 253 | New OUTPUT option delivers template results directly to a |
| 254 | filehandle instead of making them into a string. Saves space |
| 255 | and time. |
| 256 | |
| 257 | PACKAGE and HASH now work intelligently with SAFE. |
| 258 | |
| 259 | Fragments may now output data directly to the template, rather |
| 260 | than having to arrange to return it as a return value at the |
| 261 | end. This means that where you used to have to write this: |
| 262 | |
| 263 | { my $blist = ''; |
| 264 | foreach $i (@items) { |
| 265 | $blist .= qq{ * $i\n}; |
| 266 | } |
| 267 | $blist; |
| 268 | } |
| 269 | |
| 270 | You can now write this instead, because $OUT is special. |
| 271 | |
| 272 | { foreach $i (@items) { |
| 273 | $OUT.= " * $i\n"; |
| 274 | } |
| 275 | } |
| 276 | |
| 277 | (`A spoonful of sugar makes the medicine go down.') |
| 278 | |
| 279 | Fixed some small bugs. Worked around a bug in Perl that does |
| 280 | the wrong thing with $x = <Y> when $x contains a glob. |
| 281 | |
| 282 | More documentation. Errors fixed. |
| 283 | |
| 284 | Lots more tests. |
| 285 | |
| 286 | ---------------------------------------------------------------- |
| 287 | |
| 288 | What's new in v1.03 since v1.0: |
| 289 | |
| 290 | Code added to support HASH option to fill_in. |
| 291 | (Incl. `_gensym' function.) |
| 292 | |
| 293 | Documentation for HASH. |
| 294 | |
| 295 | New test file for HASH. |
| 296 | |
| 297 | Note about failure of lexical variables to propagate into |
| 298 | templates. Why does this surprise people? |
| 299 | |
| 300 | Bug fix: program fragments are evaluated in an environment with |
| 301 | `no strict' by default. Otherwise, you get a lot of `Global |
| 302 | symbol "$v" requires explicit package name' failures. Why didn't |
| 303 | the test program pick this up? Because the only variable the test |
| 304 | program ever used was `$a', which is exempt. Duhhhhh. |
| 305 | |
| 306 | Fixed the test program. |
| 307 | |
| 308 | Various minor documentation fixes. |
| 309 | |
| 310 | |
| 311 | |
| 312 | ---------------------------------------------------------------- |
| 313 | |
| 314 | Improvements of 1.0 over the old 0.1beta: |
| 315 | |
| 316 | New features: |
| 317 | |
| 318 | At least twice as fast |
| 319 | |
| 320 | Better support for filling out the same template more than once |
| 321 | |
| 322 | Now supports evaluation of program fragments in Safe |
| 323 | compartments. (Thanks, Jonathan!) |
| 324 | |
| 325 | Better argument syntax |
| 326 | |
| 327 | More convenience functions |
| 328 | |
| 329 | The parser is much better and simpler. |
| 330 | |
| 331 | Once a template is parsed, the parsed version is stored so that |
| 332 | it needn't be parsed again. |
| 333 | |
| 334 | BROKEN function behavior is rationalized. You can now pass an |
| 335 | arbitrary argument to your BROKEN function, or return a value |
| 336 | from it to the main program. |
| 337 | |
| 338 | Documentation overhauled. |
| 339 | |