Keep the parsed pattern property keys

schema.go

@@ -321,14 +321,14 @@ func (d *Schema) parseSchema(documentNode interface{}, currentSchema *subSchema)
 			if len(patternPropertiesMap) > 0 {
 				currentSchema.patternProperties = make(map[string]*subSchema)
 				for k, v := range patternPropertiesMap {
-					_, err := regexp.MatchString(k, "")
+					re, err := regexp.Compile(k)
 					if err != nil {
 						return errors.New(formatErrorDescription(
 							Locale.RegexPattern(),
 							ErrorDetails{"pattern": k},
 						))
 					}
-					newSchema := &subSchema{property: k, parent: currentSchema, ref: currentSchema.ref}
+					newSchema := &subSchema{property: k, parent: currentSchema, ref: currentSchema.ref, patternPropertyKey: re}
 					err = d.parseSchema(v, newSchema)
 					if err != nil {
 						return errors.New(err.Error())

subSchema.go

@@ -124,6 +124,7 @@ type subSchema struct {
 	dependencies         map[string]interface{}
 	additionalProperties interface{}
 	patternProperties    map[string]*subSchema
+	patternPropertyKey   *regexp.Regexp
 	propertyNames        *subSchema
 
 	// validation : array

validation.go

@@ -29,7 +29,6 @@ import (
 	"encoding/json"
 	"math/big"
 	"reflect"
-	"regexp"
 	"strconv"
 	"strings"
 	"unicode/utf8"
@@ -687,8 +686,8 @@ func (v *subSchema) validatePatternProperty(currentSubSchema *subSchema, key str
 
 	validated := false
 
-	for pk, pv := range currentSubSchema.patternProperties {
-		if matches, _ := regexp.MatchString(pk, key); matches {
+	for _, pv := range currentSubSchema.patternProperties {
+		if pv.patternPropertyKey != nil && pv.patternPropertyKey.MatchString(key) {
 			validated = true
 			subContext := NewJsonContext(key, context)
 			validationResult := pv.subValidateWithContext(value, subContext)