protected SourceDocumentEdit(ISourceLocation sourceLocationBeforeEdit, ISourceDocument sourceDocumentAfterEdit) { Contract.Requires(sourceLocationBeforeEdit != null); Contract.Requires(sourceDocumentAfterEdit != null); Contract.Requires(sourceDocumentAfterEdit.IsUpdatedVersionOf(sourceLocationBeforeEdit.SourceDocument)); this.sourceLocationBeforeEdit = sourceLocationBeforeEdit; this.sourceDocumentAfterEdit = sourceDocumentAfterEdit; }