public StepArgumentMatcher(string regularExpression, ICandidateStepSource candidateStepSource)
 {
     this.candidateStepSource = candidateStepSource;
     this.regularExpression = regularExpression;
 }
 public StepArgumentSource(ICandidateStepSource candidateStepSource)
 {
     this.candidateStepSource = candidateStepSource;
 }