import { UpdateType } from '@typedorm/common' ; import { BaseExpressionInput } from '../base-expression-input' ; export class Update extends BaseExpressionInput { protected prefix = '' ; protected getExpNameKey ( key ) { return `#UE_${ key }` ; } protected getExpValueKey ( key ) { return `:UE_${ key }` ; } @override and
      and ( ) { this . expression += ', ' ; return this ; } @override or
      or ( ) { throw new Error ( '"or" operation is not supported with update expression.' ) ; } @override merge
      merge ( update ) { const { expression , names , values , prefix } = update ; if ( ! prefix ) { throw new Error ( 'Can not merge with Base `Update` type, merging expression must have a valid prefix.' ) ; } if ( ! expression ) { return this ; } if ( update . constructor === this . constructor ) { this . expression += this . expression ? ',' : '' ; this . appendToExpression ( expression ) ; } else { this . appendToExpression ( `${ prefix } ${ expression }` ) ; } this . names = { ... this . names , ... names } ; this . values = { ... this . values , ... values } ; return this ; } @override  mergeMany
      mergeMany < T = this > ( inputs ) { const merged = inputs . reduce ( ( acc , upd ) => { acc . merge ( ( upd as unknown ) as this ) ; return acc ; } , this ) ; return merged ; } protected getSymbolForArithmeticOperator ( operator ) { const symbolMap = { INCREMENT_BY : '+' , DECREMENT_BY : '-' , } ; return symbolMap [ operator ] ; } }