ErlyDTL
=======
ErlyDTL implements most but not all of the Django Template Language.
Project homepage: <http://code.google.com/p/erlydtl/>
Compilation
-----------
To compile ErlyDTL, run
make
in this directory.
Template compilation
--------------------
Four ways:
erlydtl:compile("/path/to/template.dtl", my_module_name)
erlydtl:compile("/path/to/template.dtl", my_module_name, Options)
erlydtl:compile(<<"<html>{{ foo }}</html>">>, my_module_name)
erlydtl:compile(<<"<html>{{ foo }}</html>">>, my_module_name, Options)
Options is a proplist possibly containing:
* `out_dir` - Directory to store generated .beam files. If not specified, no
.beam files will be created.
* `doc_root` - Included template paths will be relative to this directory;
defaults to the compiled template's directory.
* `custom_tags_dir` - Directory of DTL files (no extension) includable as tags.
E.g. if $custom_tags_dir/foo contains `<b>{{ bar }}</b>`, then `{% foo bar=100 %}`
will evaluate to `<b>100</b>`. Get it?
* `custom_tags_module` - A module to be used for handling custom tags. Each custom
tag should correspond to an exported function, e.g.:
some_tag(Variables, TranslationFun) -> iolist()
* `vars` - Variables (and their values) to evaluate at compile-time rather than
render-time.
* `reader` - {module, function} tuple that takes a path to a template and returns
a binary with the file contents. Defaults to `{file, read_file}`. Useful
for reading templates from a network resource.
* `compiler_options` - Proplist passed directly to `compiler:forms/2`
* `force_recompile` - Recompile the module even if the source's checksum has not
changed. Useful for debugging.
* `locale` - The locale used for template compile. Requires erlang_gettext. It
will ask gettext_server for the string value on the provided locale.
For example, adding {locale, "en_US"} will call {key2str, Key, "en_US"}
for all string marked as trans (`{% trans "StringValue" %}` on templates).
See README_I18N.
Helper compilation
------------------
Helpers provide additional templating functionality and can be used in
conjunction with the `custom_tags_module` option above. They can be created
from a directory of templates thusly:
erlydtl:compile_dir("/path/to/dir", my_helper_module_name)
erlydtl:compile_dir("/path/to/dir", my_helper_module_name, Options)
The resulting module will export a function for each template appearing
in the specified directory. Options is the same as for compile/3.
Compiling a helper module can be more efficient than using `custom_tags_dir`
because the helper functions will be compiled only once (rather than once
per template).
Usage (of a compiled template)
------------------------------
my_compiled_template:render(Variables) -> {ok, IOList} | {error, Err}
Variables is a proplist, dict, gb_tree, or a parameterized module
(whose method names correspond to variable names). The variable
values can be atoms, strings, binaries, or (nested) variables.
IOList is the rendered template.
my_compiled_template:render(Variables, TranslationFun) ->
{ok, IOList} | {error, Err}
Same as `render/1`, but TranslationFun is a fun/1 that will be used to
translate strings appearing inside `{% trans %}` tags. The simplest
TranslationFun would be `fun(Val) -> Val end`
my_compiled_template:translatable_strings() -> [String]
List of strings appearing in `{% trans %}` tags that can be overridden
with a dictionary passed to `render/2`.
my_compiled_template:source() -> {FileName, CheckSum}
Name and checksum of the original template file.
my_compiled_template:dependencies() -> [{FileName, CheckSum}]
List of names/checksums of templates included by the original template
file. Useful for frameworks that recompile a template only when the
template's dependencies change.
Tests
-----
From a Unix shell, run:
make test
Note that the tests will create some output in examples/rendered_output.
