Supports:
- Closure syntax: `(x, y) => z`
- Shorthand for a single argument: `x => y`
- Function syntax: `let f(x) = y`
- Capturing of variables from the environment
- Error messages for too few / many passed arguments
Does not support:
- Named arguments
- Variadic arguments with `..`
This extension enables you to
- quickly open the actual and reference output for a test case to the side
- re-run the test with the click of a button
- approve the test output (moves output to reference folder and optimizes with oxipng)
