Example:

    GTM>K S (a(1),a(2000),a("CAT"),a("cat"),a("ALF"), a(12))=1
    GTM>S x="" F S x=$0(a(x)) U:x="" W !,x
    1
    12
    2000
    ALF
    CAT
    cat
    GTMK> a("CAT") SET a(5,10)="woolworths",a("cat")="last"
    GTM> S x="" F S x=$O(a(x),-1) Q:x="" W !,x
    cat
    ALF
    2000
    12
    5
    1
    GTM>    
    

This example uses a $ORDER() loop to display all the subscripts at the first level of local variable a, make some changes in a, and then display all the subscripts in reverse order. Notice that $ORDER() returns only the existing subscripts in the sparse array and returns them in M collation sequence, regardless of the order in which they were entered. Also, $ORDER() does not differentiate between node A(5), which has only descendants (no data value), and the other nodes, which have data values.

Example:

    GTM>k s (%(1),tiva(2),A(3),tiv(4),Q(5),%a(6))=""
    GTM>s x="%"
    GTM>w:$d(@x) !,x f s x=$order(@x) q:x="" w !,x
    %
    %a
    A
    Q
    tiv
    tiva
    x
    GTM>s x="zzzzzzzz"
    GTM>w:$d(@x) !,x f s x=$order(@x,-1) q:x="" w !,x
    x
    tiva
    tiv
    Q
    A
    %a
    %
    GTM>    
    

This loop uses $ORDER() to display the current local variable names in both forward and reverse order. Notice that the first ([^]%) and last ([^]zzzzzzzz) names require handling as special cases and require a $DATA() function.

Example:

    SET acct="",cntt=""
    FOR SET acct=$OREDER(^acct(acct)) QUIT:acct="" DO
    . F SET cntt=$ORDER(^acct(acct,cntt)) DO WORK
    QUIT
    

This uses two nested $ORDER() loops to cycle through the ^acct global array and perform some action for each second level node.