Variables
You can declare a variable in one of the following ways:
- Pass it in the settings when building documentation.
- Describe it in a file with variable presets.
Methods for using variables in documents are discussed below.
Substitutions
To substitute a value with a variable in the text, enter the variable name with double curly brackets before and after.
Some text not_var{{ variable_name }} text continued.
If the text contains double curly brackets but doesn't require variable substitution, add not_var before the construction.
Some text not_varnot_var{{ also_text }} text continued.
Conditional operators
Use the conditional operators if, else, and elsif to include certain text fragments in the document depending on variable values. For example, to build two versions of a document for different operating systems.
{% if OS == 'iOS' %}
Download the app from the [App Store](https://www.apple.com/ios/app-store/).
{% else %}
Download the app from [Google Play] (https://play.google.com).
{% endif %}
You can also apply conditional operators to text fragments inside strings.
Some text {% if OS == 'iOS' %} Apple {% else %} Android {% endif %} text continued.
Cycles
Use loops to output repetitive content for each element of an array. Inside the loop, refer to the element as a regular variable, using syntax for substitutions.
{% for variable_name in array_name %}
Some text not_var{{ variable_name }} text continued.
{% endfor %}
Examples of using loops
Let's say that in a file with variable presets, the users array is set:
default:
users:
- Alice
- Mark
Then using loops will result in the following:
Prefix {% for user in users %} not_var{{user}} {% endfor %} Postfix
Prefix Alice Mark Postfix
Prefix
{% for user in users %}
not_var{{user}}
{% endfor %}
Postfix
Prefix
Alice
Mark
Postfix
Filters
To apply a filter, add the | operator and the filter name to the variable. Separate the operator with spaces before and after.
| Filter | Description |
|---|---|
capitalize |
Makes the first letter in the variable value upper case. |
length |
Calculates the length of the variable value. |
Examples of using filters
Let's say the following is set in a file with variable presets:
default:
user:
name: alice
users:
- Alice
- Mark
Then using filters will result in the following:
Hello not_var{{ user.name | capitalize }}!
Hello Alice!
not_var{{ users | length }}
not_var{{ user.name | length }} | length
2
5
Functions
To invoke a function, add the . symbol to the variable, specify its name, and pass the necessary parameters in parentheses ().
| Function | Description | Parameters |
|---|---|---|
slice(beginIndex, endIndex) |
Returns the specified part of the source array as a new array object. | beginIndex is an index of the element the selection begins with (numbering starts with 0).endIndex is an index of the element the selection ends with (numbering starts with 0). If the parameter is omitted, all elements from the starting position to the end of the array are selected. |
Examples of using functions
Let's say the following is set in a file with variable presets:
default:
user:
name: Masha
Then using functions will result in the following:
Hello Pnot_var{{ user.name.slice(1) }}!
Hello Pnot_var{{ user.name.slice(1, 2) }}vel!
Hello Pasha!
Hello Pavel!