nv-facutil-switch v0.0.3

nv-facutil-switch

• nv-facutil-switch is a simple-util to avoid using-of-switch-case
• support async matcher AND async handler
• if match, the default-action-after-handle is break, NOT continue

• switch-case normally can only be changed in COMPILE-TIME, it's NOT convinient
• switch-case is HARD(maybe impossible) to auto-dynamic-handle in RUNTIME

install

• npm install nv-facutil-switch

usage

 const {
     cmmn,
     creat_sync_simple_switch,
     creat_async_simple_switch,
     creat_sync_simple_switch_cache,
     creat_async_simple_switch_cache,
     creat_sync_nest_switch,
     creat_async_nest_switch,
     creat_sync_nest_switch_cache,
     creat_async_nest_switch_cache,
 } = require("nv-facutil-switch");

example

nest

• creat_SYNC_nest_switch support-only-SYNC-matcher-and-handler, but performance better
• creat_ASYNC_nest_switch support-both-SYNC-AND-ASYNC-matcher-and-handler

    //completion                   break-OR-continue
         ----default is break , NOT continue!!!!

    //CASE                         [matcher, handler,completion]

    //DEFAULT                      {matcher, handler}
        //----if DEFAULT     exist ,completion always be BREAK
    
    //EMPTY
    
    //SWITCHER
    [
       <CASE     | SWITCHER>,
       .....
       <CASE     | SWITCHER>,
       <DEFAULT  |   EMPTY>
    ]




    const tmoutp = require('timers/promises').setTimeout;


    var dflt_handler = (r)=>'invalid'

    var entries = [//switch@root
        [(r)=>r%6===0, (r)=>r,  /*default:cmmn.break*/],
        [
            (r)=>r%6===1,
            [ //switch1@child
                [(r)=>r%7===0,                            (r)=>r,             /*default:cmmn.break*/],
                [async(r)=>tmoutp(5000,r%7===1),          (r)=>r,             /*default:cmmn.break*/],
                [(r)=>r%7===2,                            (r)=>r,             /*default:cmmn.break*/],
                {handler:(r)=>'invalid' ,completion:cmmn.break/*default:cmmn.break*/}                        //default CASE of switch1@child
            ],
            cmmn.break                                         // this could be omitted,/*default:cmmn.break*/
        ],
        [(r)=>r%6===2, (r)=>r,  /*default:cmmn.break*/],
        [
            (r)=>r%6===3,
            [//switch2@child
                [(r)=>r<50,          (r)=>r,             /*default:cmmn.break*/]
                //switch2@child without default CASE
            ],
            cmmn.break                            // this could be omitted,/*default:cmmn.break*/
        ],
        {handler:async(r)=>tmoutp(5000,`invalid-last`), completion: cmmn.break /*default:cmmn.break*/}                      //default CASE of switch@root
    ]




    var ANestSwitch = creat_async_nest_switch(entries,dflt_handler)
    var switcher = new ANestSwitch()

;

    await switcher.handle(6)
    await switcher.handle(7)
    await switcher.handle(31)
    await switcher.handle(8)
    await switcher.handle(63)
    await switcher.handle(33)
    await switcher.handle(34)

    /*
    > await switcher.handle(6)
    6
    > await switcher.handle(7)
    7
    > await switcher.handle(31)
    'invalid'
    > await switcher.handle(8)
    8
    > await switcher.handle(63)
    undefined
    > await switcher.handle(33)
    33
    > await switcher.handle(34)
    'invalid-last'
    >

    */

nest-cache

simple

• creat_SYNC_simple_switch support-only-SYNC-matcher-and-handler, but performance better
• creat_ASYNC_simple_switch support-both-SYNC-AND-ASYNC-matcher-and-handler

    const tmoutp = require('timers/promises').setTimeout;


    //ENTRY   [match-function, handle-function, completion]
    //        ----completion COULD-BE break-OR-continue ,
    //        ----default is break , NOT continue!!!!

    var entries = [
        [(r)=>r===0,                         (r)=>0,                      /*default:cmmn.break*/],
        [(r)=>r===1,                         async(r)=>tmoutp(5000,100),  /*default:cmmn.break*/],
        [ async(r)=>tmoutp(5000,r===2),      (r)=>200,                    /*default:cmmn.break*/],
    ]

    var dflt_handler = (r)=>'invalid'


    var SimpleSwitch = creat_async_simple_switch(entries,dflt_handler)
    var switcher = new SimpleSwitch()

    await switcher.handle(0)
    //0
    await switcher.handle(1)
    //100
    await switcher.handle(2)
    //200
    await switcher.handle(3)
    //'invalid'
    await switcher.handle(4)
    //'invalid'
    

    > await switcher.handle_rtrn_$breaker_handler_index_matcher$(1)
            {
              index: 1,
              matcher: [Function (anonymous)],
              handler: [AsyncFunction (anonymous)],
              breaker: true
            }

    >

simple-cache

    var entries = [
        [(r)=>r%3===0,                         (r)=>0,                      /*default:cmmn.break*/ ],
        [(r)=>r%3===1,                         async(r)=>tmoutp(5000,100),  /*default:cmmn.break*/ ],
        [ async(r)=>tmoutp(5000,r%3===2),      (r)=>200,                    /*default:cmmn.break*/ ],
    ]

    var dflt_handler = (r)=>'invalid'
    
    
    var SimpleSwitchCache = creat_async_simple_switch_cache(entries,dflt_handler)
    var switcher = new SimpleSwitchCache()
    
    await switcher.handle(5)
    await switcher.handle(13)
    await switcher.handle(6)
    await switcher.handle(7)
    await switcher.handle(87)
    
    var matcher1 = entries[1][0]
    matcher1
    
    > switcher.group(matcher1) 
    [ 13, 7 ]
    >

    > switcher.group_cache_
    [ [ 6, 87 ], [ 13, 7 ], [ 5 ] ]
    >
    
    > switcher.reset_group_cache()
    > switcher.group_cache_
    [ [], [], [] ]
    >

METHODS

nest

switcher._handle               switcher.dflt_handler_
switcher.gen                   switcher.handle                switcher.src_
switcher.tree_

nest-cache

    switcher._handle               switcher.constructor           switcher.dflt_cases_
    switcher.dflt_handler_         switcher.gen                   switcher.group_cache_
    switcher.handle                switcher.handlers_             switcher.matchers_
    switcher.reset_group_cache     switcher.src_                  switcher.tree_

simple

    switcher._handle                                      switcher.breaker
    switcher.breakers_                                    switcher.constructor
    switcher.dflt_handler_                                switcher.handle
    switcher.handle_rtrn_$breaker$                        switcher.handle_rtrn_$breaker_handler$
    switcher.handle_rtrn_$breaker_handler_index$          switcher.handle_rtrn_$breaker_handler_index_matcher$
    switcher.handle_rtrn_$breaker_handler_matcher$        switcher.handle_rtrn_$breaker_index$
    switcher.handle_rtrn_$breaker_index_matcher$          switcher.handle_rtrn_$breaker_matcher$
    switcher.handle_rtrn_$handler$                        switcher.handle_rtrn_$handler_index$
    switcher.handle_rtrn_$handler_index_matcher$          switcher.handle_rtrn_$handler_matcher$
    switcher.handle_rtrn_$index$                          switcher.handle_rtrn_$index_matcher$
    switcher.handle_rtrn_$matcher$                        switcher.handler
    switcher.handlers_                                    switcher.idxes
    switcher.matcher                                      switcher.matchers_
    switcher.src_

simple-cache

    switcher._handle                                      switcher.breaker
    switcher.breakers_                                    switcher.constructor
    switcher.dflt_handler_                                switcher.group
    switcher.group_cache_                                 switcher.handle
    switcher.handle_rtrn_$breaker$                        switcher.handle_rtrn_$breaker_handler$
    switcher.handle_rtrn_$breaker_handler_index$          switcher.handle_rtrn_$breaker_handler_index_matcher$
    switcher.handle_rtrn_$breaker_handler_matcher$        switcher.handle_rtrn_$breaker_index$
    switcher.handle_rtrn_$breaker_index_matcher$          switcher.handle_rtrn_$breaker_matcher$
    switcher.handle_rtrn_$handler$                        switcher.handle_rtrn_$handler_index$
    switcher.handle_rtrn_$handler_index_matcher$          switcher.handle_rtrn_$handler_matcher$
    switcher.handle_rtrn_$index$                          switcher.handle_rtrn_$index_matcher$
    switcher.handle_rtrn_$matcher$                        switcher.handler
    switcher.handlers_                                    switcher.idxes
    switcher.matcher                                      switcher.matchers_
    switcher.reset_group_cache                            switcher.src_

LICENSE

• ISC