Query Templates

  "substitutions": [
    {
      "target": "{@escape@}",
      "file": "escape.boa"
    },
    {
      "target": "{@project-filter@}",
      "replacement": "if (input.stars >= 5)"
    }
  ],

Query templates are defined through a list of substitutions. Substitutions are defined using two keys. The target key is mandatory, containing the text which is replaced in the query. Targets must start with {@ and end with @}. Target names are restricted to alphanumeric characters, and some special characters like -_:.. Then, either replacement or file are used, with replacement providing the text directly, and file being the name of a file under boa/snippets/ which replaces target. Care must be taken to ensure that the query is valid Boa code after substitution is completed.

Before performing substitutions, a substitutions list is constructed, first from local substitutions then from global substitutions. If two substitutions define the same target, the first one defined is used. Substitution will iterate through the substitutions list until a loop has been completed without any substitutions (i.e., a steady state has been reached).