What kind statement should I use if I need to loop?

[huangchenmin]

Hello everyone
I need to loop to beginneing of routine. Fail to use loop statement.
What can I do ?
Followings are example
#include "hmg.ch"
function main()
Local m_switch:=.F.
if m_switch
Msginfo("Now m_switch is .T."+chr(13)+chr(10)+"Next gonna call inner()")
inner()
else
m_switch:=.T.
Msginfo("Now m_switch is .F."+chr(13)+chr(10)+"Next gonna loop")
loop
endif
return
function inner()
Msginfo("Now in inner(),loop is useable!")
return

[dhaine_adp]

Please clarify if you are talking about recursion. You cannot do loops on the sample code that you have provided.

It's either you use do..while or for...next statement or use recursive call.

[esgici]

I need to loop to beginneing of routine. Fail to use loop statement.

Hi Chen Min

As EXIT statement (opposite in meaning), LOOP statement is usable and meaningful into [DO] WHILE ... ENDDO and FOR ... NEXT loop structure. So it can't be usable out or without of these loop statements structure.

From CL52E Documentation:

Code: Select all

DO WHILE
 Execute a loop while a condition is true (.T.)
 -------------------------------------------------------------------
 Syntax

     [DO] WHILE <lCondition>
        <statements>...
        [EXIT]
        <statements>...
        [LOOP]
        <statements>...
     END[DO]

 Arguments

     <lCondition> is the logical control expression for the DO WHILE
     loop.

     EXIT unconditionally branches control from within a DO WHILE or
     FOR...NEXT structure to the statement immediately following the
     corresponding ENDDO or NEXT statement.

     LOOP branches control to the most recently executed DO WHILE or FOR
     statement.

 Description

     DO WHILE...ENDDO is a control structure that executes a block of
     statements repetitively, as long as <lCondition> evaluates to true (.T.).
     When the condition evaluates to true (.T.), control passes into the
     structure and proceeds until an EXIT, LOOP, or ENDDO is encountered.
     ENDDO returns control to the DO WHILE statement and the process repeats
     itself.  If an EXIT statement is encountered, control branches to the
     nearest ENDDO or NEXT statement.  If a LOOP statement is encountered,
     control branches to the nearest DO WHILE or FOR statement.  If the
     condition evaluates to false (.F.), the DO WHILE construct terminates and
     control passes to the statement immediately following the ENDDO.

     Use EXIT to terminate a DO WHILE structure based on a condition other
     than the DO WHILE condition.  LOOP, by contrast, prevents execution of
     statements within a DO WHILE based on an intermediate condition, and
     returns to the most recent DO WHILE statement.

     DO WHILE constructs may be nested within any other control structures to
     any depth.  The only requirement is that each control structure be
     properly nested.

 Examples

     This example demonstrates a typical control structure for a
     simple grouped report:

        LOCAL cOldSalesman, nTotalAmount
        USE Sales INDEX Salesman NEW
        DO WHILE .NOT. EOF()
           cOldSalesman := Sales->Salesman
           nTotalAmount := 0
           DO WHILE cOldSalesman = Sales->Salesman ;
              .AND. (.NOT. EOF())
              ? Sales->Salesman, Sales->Amount
              nTotalAmount := nTotalAmount + Sales->Amount
              SKIP
           ENDDO
           ? "Total: ", nTotalAmount, "for", cOldSalesman
        ENDDO
        CLOSE Sales

     This code fragment demonstrates how LOOP can be used to
     provide an intermediate processing condition:

        DO WHILE <lCondition>
           <initial processing>...
           IF <intermediate condition>
              LOOP
           ENDIF
           <continued processing>...
        ENDDO

     This example demonstrates the use of DO WHILE to emulate a
     repeat until looping construct:

        LOCAL lMore := .T.
        DO WHILE lMore
           <statements>...
           lMore := (<lCondition>)
        ENDDO

     This example uses a DO WHILE loop to move sequentially through
     a database file:

     DO WHILE .NOT. EOF()
        <statements>...
        SKIP
     ENDDO

I hope that this will help you.

Happy HMG'ing

Regards

--

Esgici

[huangchenmin]

Please clarify if you are talking about recursion. You cannot do loops on the sample code that you have provided.

It's either you use do..while or for...next statement or use recursive call.

Thanks for your supports!
recursion is a good ideal.