Std.Text.Parse.label
1 declaration
fn
label: Str -> 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
Say what a parser wanted, in the reader's words rather than the grammar's.
Replaced only where the parser failed without consuming. A parser that read
part of what it wanted has already told a more precise story, and covering
it with the outer name would lose where the trouble was.
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.