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Fixed transpilation of "True", "False" and "Unit".

Christian Rinderknecht requested to merge rinderknecht@transpilation_ctor into dev

Motivation and Context

The CST-to-CST transpilation from PascaLIGO to JsLIGO was incorrect on values for the predefined data constructors True, False and Unit. With this MR we transpile

const _ = case x of [True -> 0 | False -> 1]
const _ = case y of [A -> True | B -> False]


const _ = match(x, { True: () => 0, False: () => 1 });

const _ = match(y, { A: () => true, B: () => false });

The boolean values in patterns remain unchanged (True and False) because of technical difficulties in the pipeline. We argue that matching on those values is bad style, as a conditional is best. Moreover, we do not have deep pattern matching is JsLIGO, so conditionals should be the obvious choice.



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Types of changes

  • Bug fix (non-breaking change which fixes an issue)
  • New feature (non-breaking change which adds functionality)
  • Breaking change (fix or feature that would cause existing functionality to not work as expected)
  • Performance improvement (non-breaking change that improves performance)
  • None (change with no changelog)


Fixed transpilation from PascaLIGO to JsLIGO of predefined data constructors "True", "False" and "Unit" as values (patterns remain unchanged).


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  • Changes follow the existing coding style (use dune @fmt to check).
  • Tests for the changes have been added (for bug fixes / feature).
  • Documentation has been updated.
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  • Start titles under ## Changelog section with #### (if appropriate).
  • There is no image or uploaded file in changelog
  • Examples in changed behaviour have been added to the changelog (for breaking change / feature).
Edited by Christian Rinderknecht

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