Function byPattern

expr/example.go:231–241

byPattern generates a random value that satisfies the pattern. Note: if multiple patterns are given, only one of them is used.

(a *AttributeExpr, r *ExampleGenerator)

//
// Note: if multiple patterns are given, only one of them is used.
func byPattern(a *AttributeExpr, r *ExampleGenerator) any {
	if !hasPatternValidation(a) {
		return false
	}
	pattern := a.Validation.Pattern
	re, err := syntax.Parse(pattern, syntax.Perl)
	if err != nil {
		return r.Name()
	}
	return patgen(re.Simplify(), r)
}

func patgen(re *syntax.Regexp, r *ExampleGenerator) string {
	switch re.Op {