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Question Eduard Lebedyuk · Apr 15, 2019

CacheGlobalOrder example to iterate over global and get data

#Caché #C++ #Callout

I managed to use CacheGlobalOrder to iterate over global and return the next subscript:

int GetGlobalStr(char *global, int subscript, CACHE_EXSTRP result)
{
    int push = CACHEPUSHGLOBAL(strlen(global), global);
    int pushS = CACHEPUSHINT(subscript);
    
    // narg Number of subscript expressions pushed onto the argument stack.
    int narg = 1;

    // Direction for the $Order is 1 for forward, -1 for reverse.
    int dir = 1;
    // Indicates whether the data value, if there is one, should be returned.
    int valueflag = 0;
    int order = CACHEGLOBALORDER(narg,  dir, valueflag);

    int pop = CACHEPOPEXSTR(result);
    //pop = CACHEPOPEXSTR(result);

    return ZF_SUCCESS;
}

I'm using valueflag = 0. so data is not returned, only next subscript. However, it I set valueflag to 1 I don't receive global data or next subscript, only 1 or 0 depending on whenever next key exists.

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Eduard Lebedyuk · Apr 18, 2019

Working code:

int GetGlobalOrder(char *global, int start, int end, CACHE_EXSTRP result)
{
    if (isInitialized == false) {
        Initialize(NULL);
    }

    // narg Number of subscript expressions pushed onto the argument stack.
    int narg = 1;

    // Direction for the $Order is 1 for forward, -1 for reverse.
    int dir = 1;
    // Indicates whether the data value, if there is one, should be returned.
    int valueflag = 1;

    // Has argument flag
    int flag = 0;

    // key - current subscript
    int key = start - 1;
    
    // row count
    int c=0;

    while (key<end) {
        CACHEPUSHGLOBAL(strlen(global), global);
        CACHEPUSHINT(key);
        CACHEGLOBALORDER(narg,  dir, valueflag);

        CACHEPOPINT(&flag);
        if (flag) {
          //use CACHETYPE() to get the value type, then the appropriate CACHEPOP for the subscript
          CACHEEXSTRKILL(result);
          CACHEPOPEXSTR(result);
          // do stuff with result
        }
        //use CACHETYPE() to get the subscript type, then the appropriate CACHEPOP for the subscript
        int type = CACHETYPE();

        CACHEPOPINT(&key);

        if (key==NULL) {
            break;
        }

        c++;
    }
    return ZF_SUCCESS;
}

Thanks to @Charles.SorensonIIfor help!

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