how to reference a YAML "setting" from elsewhere in the same YAML file?

syntax yaml template-engine transclusion
Andrew Bullock picture Andrew Bullock · Jan 14, 2010 · Viewed 110.6k times · Source

I have the following YAML:

paths:
  patha: /path/to/root/a
  pathb: /path/to/root/b
  pathc: /path/to/root/c

How can I "normalise" this, by removing /path/to/root/ from the three paths, and have it as its own setting, something like:

paths:
  root: /path/to/root/
  patha: *root* + a
  pathb: *root* + b
  pathc: *root* + c

Obviously that's invalid, I just made it up. What's the real syntax? Can it be done?

Answer

vava picture vava · Jan 14, 2010

I don't think it is possible. You can reuse "node" but not part of it. 

bill-to: &id001
    given  : Chris
    family : Dumars
ship-to: *id001

This is perfectly valid YAML and fields given and family are reused in ship-to block. You can reuse a scalar node the same way but there's no way you can change what's inside and add that last part of a path to it from inside YAML.

If repetition bother you that much I suggest to make your application aware of root property and add it to every path that looks relative not absolute.

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