The package provides configuration loader and pre-defined resolver.

An configuration example:

_vars:
  window:
    width: 800
    height: 600
app:
  - name: message-layer
    properties:
      window:
        image: resources/window-base.png
        position:
          x: 0
          y: ${${var:window.height} - ${ref:..size.height}}
        size:
          width: ${var:window.width}
          height: 150

Syntax

_vars

You can define a new variable. Use object syntax under the _vars field.

The variables can be referenced in all siblings and under their siblings to the _vars, in the variable syntax ${var:_path_}.

Expr

In each field, you can specify an expression defined in the loader.

• ${}: enclose the expr by ${}, to tell the parsers that the field is an expr not a plain string.
• ${ref:_path_}: specify any path to refer any other value. The path resolution is performed once, not recursively resolved. _path_ consists of field names splitted by a period. Use double dots .. for a parent.
• ${var:_path_}: specify any path to value defined at the field. _path_ consists of field names splitted by a period.
• arithmetic operator: addition, subtraction, multiplication and division (+,-,*,/) can also be used in ${}.