Function swipl::result::attempt_opt

source · 
pub fn attempt_opt<R>(r: PrologResult<R>) -> OptPrologResult<R>
Expand description

Transforms a PrologResult into an OptPrologResult, allowing more easy use from an if block.

Example:

    if let Some(num) = attempt_opt(term.get::<u64>())? {
        // term contained an u64
    } else {
        // term did not contain an u64
    }