The template files are compiled into C files that can then be compiled with the rest of the application. To access the template code the `template.h` file is used (see "Using Templates").
## Building
`make all` will build the executeable for translating the templates and the static library that includes the template registry.
## Dependencies & Compatibility
Besides a C compiler `lex` and `yacc` are also required. The `Makefile` uses `flex` and `bison` respecively but I think I only used non-specific features.
As for the C compiler support for GNU function attributes is needed. So `gcc` or `clang` should work, maybe others as well.
# Usage
## Template Format
Template files have the following syntax:
```
[meta section]
%%
[main section]
```
The meta section can contain the parameter list for the template as well as static statement blocks for optional includes, definitions, ...
The main section contains the content of the template. Here statement blocks and output blocks are allowed.
Note: All types that C does not provide by default have to be declared in a statement block in the meta section or in a header file included by a statement block in the meta section. In the example above this would apply to the type `user_t`.
Note: In case of pointer parameters they are not allowed to be modified in statement or output blocks. If the template has side effects like that, the behavior might be undefined (because of the calculation of the the output size).
In the meta section these blocks can be used to define datatypes - even functions - and include any needed header files. Anything that got declared this way can be used as a parameter type in a parameter block.
Examples:
```
{% #include "someheader.h" %}
{%
struct s {
int i;
};
%}
```
In the main section these blocks will open a template block. This template blocks has to be closed with `{% end %}`. Statement blocks in the main section are meant to be used for loops and conditions.
Example:
```
{% for(int i = 0; i <10;i++)%}
This string will be printed 10 times.
{% end %}
```
Inside statement blocks in the main section the parameters as well as all local variables of parent statement blocks can be accessed.
At the moment there is only one structure command implemented.
## Render
Using the render command, a another template can be included at the current position. The first parameter is the name of the template to be included as a string. All following parameters will be used as template parameters.
This will translate the template in `templates/index.html.templ` using the name "templates/index.html.templ" and write the generated code to `gen/templates/index.tab.c`.
## Compiling & Linking
Just include all generated files when compiling and linking your application.
The file `templates.h` needs to be accessable in the include-path. So make sure to add the `-Isrc/` flag (change the path to the correct location).
The function `renderTemplate()` will render the template with the given name to a `FILE*`. The first argument is the name of the template, the second one is the `FILE*` into which the template will be rendered. The following arguments are the parameters of the template itself (in the order that they were declared in the template file).
The function `sizeTemplate()` will return the exact length of the output of a render. The first argument is the name of the template. The following arguments are the template parameters.
The function `renderTemplateStr()` will return a string containing the rendered template. The first argument is the name of the template. Followed by the template parameters. Note that the string is allocated on the heap - the result has to be freed manually.
