
To use translator (called by !exec), the dictionary file should be defined using
the variable $dictionary.

Words not appearing in the dictionary will be erased in the output.

Syntax of the dictionary file:

Each line defines a translation of word. The original word is written first,
followed by the character `:'. Then the translation.

The dictionary must be sorted. Original words containing other than alphabetic
characters are omitted. Original words must all be in lower case.

