Takes a compiled expression and a conversion, and if the expression is a constant,
runs the conversion once saving the converted result. This saves work if this
happens at compilation time, not runtime.
If the expression is dynamic, then
it runs the expression then the conversion once, and saves the result.
Note that the "only once" aspect of this isn't terribly important, as one would not
expect parse/unparse operations to go back and ask for these expressions repeatedly. They
should be keeping it in a local val.
Takes a compiled expression and a conversion, and if the expression is a constant, runs the conversion once saving the converted result. This saves work if this happens at compilation time, not runtime.
If the expression is dynamic, then it runs the expression then the conversion once, and saves the result.
Note that the "only once" aspect of this isn't terribly important, as one would not expect parse/unparse operations to go back and ask for these expressions repeatedly. They should be keeping it in a local val.