Cutlery/calibre
1
0
Fork 0
mirror of https://github.com/kovidgoyal/calibre.git synced 2025-07-09 03:04:10 -04:00
Code Issues Packages Projects Releases Wiki Activity

Slight improvement to manual

Browse Source
This commit is contained in:
Charles Haley 2010-10-04 10:18:41 +01:00
parent ce0de68aa0
commit 6ade149cbd
1 changed files with 3 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
src/calibre/manual/template_lang.rst
View File

@ -119,10 +119,11 @@ The functions available are:
* ``ifempty(text)`` -- if the field is not empty, return the value of the field. Otherwise return `text`. * ``ifempty(text)`` -- if the field is not empty, return the value of the field. Otherwise return `text`.
* ``test(text if not empty, text if empty)`` -- return `text if not empty` if the field is not empty, otherwise return `text if empty`. * ``test(text if not empty, text if empty)`` -- return `text if not empty` if the field is not empty, otherwise return `text if empty`.
* ``contains(pattern, text if match, text if not match`` -- checks if field contains matches for the regular expression `pattern`. Returns `text if match` if matches are found, otherwise it returns `text if no match`. * ``contains(pattern, text if match, text if not match`` -- checks if field contains matches for the regular expression `pattern`. Returns `text if match` if matches are found, otherwise it returns `text if no match`.
* ``switch(pattern, value, pattern, value, ..., else_value)`` -- for each ``pattern, value`` pair, checks if the field matches the ``pattern`` and if so, returns that ``value``. If no ``pattern`` matches, then ``else_value`` is returned. You can have as many ``pattern, value`` pairs as you want. * ``switch(pattern, value, pattern, value, ..., else_value)`` -- for each ``pattern, value`` pair, checks if the field matches the regular expression ``pattern`` and if so, returns that ``value``. If no ``pattern`` matches, then ``else_value`` is returned. You can have as many ``pattern, value`` pairs as you want.
* ``re(pattern, replacement)`` -- return the field after applying the regular expression. All instances of `pattern` are replaced with `replacement`. As in all of |app|, these are python-compatible regular expressions.
* ``shorten(left chars, middle text, right chars)`` -- Return a shortened version of the field, consisting of `left chars` characters from the beginning of the field, followed by `middle text`, followed by `right chars` characters from the end of the string. `Left chars` and `right chars` must be integers. For example, assume the title of the book is `Ancient English Laws in the Times of Ivanhoe`, and you want it to fit in a space of at most 15 characters. If you use ``{title:shorten(9,-,5)}``, the result will be `Ancient E-nhoe`. If the field's length is less than ``left chars`` + ``right chars`` + the length of ``middle text``, then the field will be used intact. For example, the title `The Dome` would not be changed. * ``shorten(left chars, middle text, right chars)`` -- Return a shortened version of the field, consisting of `left chars` characters from the beginning of the field, followed by `middle text`, followed by `right chars` characters from the end of the string. `Left chars` and `right chars` must be integers. For example, assume the title of the book is `Ancient English Laws in the Times of Ivanhoe`, and you want it to fit in a space of at most 15 characters. If you use ``{title:shorten(9,-,5)}``, the result will be `Ancient E-nhoe`. If the field's length is less than ``left chars`` + ``right chars`` + the length of ``middle text``, then the field will be used intact. For example, the title `The Dome` would not be changed.
* ``lookup(field if not empty, field if empty)`` -- like test, except the arguments are field (metadata) names, not text. The value of the appropriate field will be fetched and used. Note that because composite columns are fields, you can use this function in one composite field to use the value of some other composite field. This is extremely useful when constructing variable save paths (more later). * ``lookup(field if not empty, field if empty)`` -- like test, except the arguments are field (metadata) names, not text. The value of the appropriate field will be fetched and used. Note that because composite columns are fields, you can use this function in one composite field to use the value of some other composite field. This is extremely useful when constructing variable save paths (more later).
* ``re(pattern, replacement)`` -- return the field after applying the regular expression. All instances of `pattern` are replaced with `replacement`. As in all of |app|, these are python-compatible regular expressions.
Now, about using functions and formatting in the same field. Suppose you have an integer custom column called ``#myint`` that you want to see with leading zeros, as in ``003``. To do this, you would use a format of ``0>3s``. However, by default, if a number (integer or float) equals zero then the field produces the empty value, so zero values will produce nothing, not ``000``. If you really want to see ``000`` values, then you use both the format string and the ``ifempty`` function to change the empty value back to a zero. The field reference would be:: Now, about using functions and formatting in the same field. Suppose you have an integer custom column called ``#myint`` that you want to see with leading zeros, as in ``003``. To do this, you would use a format of ``0>3s``. However, by default, if a number (integer or float) equals zero then the field produces the empty value, so zero values will produce nothing, not ``000``. If you really want to see ``000`` values, then you use both the format string and the ``ifempty`` function to change the empty value back to a zero. The field reference would be::