Std.Text.Parse.orElse
1 declaration
fn
orElse: fn(Std.Text.Parse.Input) -> Result[(T, Std.Text.Parse.Input), Std.Text.Parse.Problem] -> fn(Std.Text.Parse.Input) -> Result[(T, Std.Text.Parse.Input), Std.Text.Parse.Problem] -> fn(Std.Text.Parse.Input) -> Result[(T, Std.Text.Parse.Input), Std.Text.Parse.Problem]This is a callable function.
What it does
The first parser, or the second when the first consumed nothing.
A parser that failed after consuming input does not fall through: the
input it read told it which branch was meant, and trying another would
report a problem from the wrong one. A caller who wants the fallback anyway
wraps the first in attempt.
Read the signature
- The text after the name is the type checked by Pudu.
- Read arrows from left to right: inputs come first, and the final type is returned.
- Names inside [ ] are type arguments, such as the item type held by a collection.
- Result makes success and recoverable failure part of the function's type.