Function facet_constraint_code 

pub fn facet_constraint_code(err: &FacetError) -> &'static str

Map a FacetError variant to its specific cvc-* constraint code

This function returns the most specific constraint code for each facet type, preferring codes like cvc-pattern-valid over generic cvc-facet-valid.

Mappings

FacetError Variant	Constraint Code
LengthViolation	cvc-length-valid
MinLengthViolation	cvc-minLength-valid
MaxLengthViolation	cvc-maxLength-valid
PatternViolation	cvc-pattern-valid
EnumerationViolation	cvc-enumeration-valid
MinInclusiveViolation	cvc-minInclusive-valid
MaxInclusiveViolation	cvc-maxInclusive-valid
MinExclusiveViolation	cvc-minExclusive-valid
MaxExclusiveViolation	cvc-maxExclusive-valid
TotalDigitsViolation	cvc-totalDigits-valid
FractionDigitsViolation	cvc-fractionDigits-valid
ExplicitTimezoneViolation	cvc-explicitTimezone-valid
InvalidPattern	cvc-pattern-valid
DerivationRestriction	cos-st-restricts
FixedFacetViolation	cos-st-restricts
ConflictingFacets	cos-st-restricts
NotApplicable	cos-applicable-facets