| This example shows how to write a lazy transformer. |
| |
| This lazy tranformer implements a ROT13 converter. ROT13 (ROTate 13) |
| is a classic substitution cipher which replaces each letter in the source |
| file with the corresponding letter 13 places later in the alphabet. |
| The source file should have a ".txt" extension and the converted file |
| is created with a ".shhhh" extension. |
| |
| Generally, only transformers that take a long time to run should be made lazy. |
| This transformer is not particularly slow, but imagine that it might be used |
| to convert the entire library of congress–laziness would then be a virtue. |
| |
| For more information, see Writing a Lazy Transformer at: |
| https://www.dartlang.org/tools/pub/transformers/lazy-transformer.html |
