Function isBindable

cel/inlining.go:220–235

isBindable indicates whether the inlined type can be used within a cel.bind() if the expression being replaced occurs within a presence test. Value types with a size() method or field selection support can be bound. In future iterations, support may also be added for indexer types which can be rewr

(matches []ast.NavigableExpr, inlined ast.Expr, inlinedType *Type)

// expression; however, this would imply a rewrite of the inlined expression that may not be necessary
// in most cases.
func isBindable(matches []ast.NavigableExpr, inlined ast.Expr, inlinedType *Type) bool {
	if inlinedType.IsAssignableType(NullType) ||
		inlinedType.HasTrait(traits.SizerType) {
		return true
	}
	for _, m := range matches {
		if m.Kind() != ast.SelectKind {
			continue
		}
		sel := m.AsSelect()
		if sel.IsTestOnly() {
			return false
		}
	}
	return true
}

// matchVariable matches simple identifiers, select expressions, and presence test expressions
// which match the (potentially) qualified variable name provided as input.