/for /next bug

dont_know_at_all · Post by **dont_know_at_all** » Tue Aug 17, 2004 3:55 am

what? are you trying to port your lame-ass C++ code to MQ2 scripting language?

Boggle.

Sparr · Post by **Sparr** » Tue Aug 17, 2004 4:00 am

no, im writing macros from scratch, then spending far too much time debugging problems in the macro caused by 'features' of the language.

dont_know_at_all · Post by **dont_know_at_all** » Tue Aug 17, 2004 4:02 am

Look at as a chance to improve your debugging skills.

Cr4zyb4rd · Post by **Cr4zyb4rd** » Tue Aug 17, 2004 4:43 am

I'm intrigued. Please post what you're doing that can't be fixed by moving things around slightly or adding and "else" clause.

Sparr · Post by **Sparr** » Tue Aug 17, 2004 4:48 am

i was looping through bazaar results.

psudocode:
/for x 1 to bazaar.count
/if bazaar.itemx.name!=nameiwant /next x
do stuff
/next x

now that i know about this problem ive fixed the code as follows:
/for x 1 to bazaar.count
/if bazaar.itemx.name==nameiwant {
do stuff
}
/next x

zanomo · Post by **zanomo** » Tue Aug 17, 2004 5:14 am

I think the result produced (2, 4, 6, 8 echoed) was perfectly correct and would be bugged if otherwise.

Tracing the codes

Code: Select all

line	statement
1	/for x 1 to 7 
2	/if (${x}%2) /next x 
3	/echo ${x} 
4	/next x

And following the statement step by step (I haven't done this for quite awhile..

):

Code: Select all

step line initial   final    if   action
          X value  X value  eval
1     1	     1       1       -     /for
2     2	     1       2     true    /if-/next x
3     1	     2       2       -     /for
4     2	     2       2     false   /if
5     3	     2       2       -     /echo 2
6     4	     2       3       -     /next x
7     1	     3       3       -     /for
8     2	     3       4     true    /if-/next x
9     1	     4       4       -     /for
10    2	     4       4     false   /if
11    3	     4       4       -     /echo 4
12    4	     4       5       -     /next x
13    1	     5       5       -     /for
14    2	     5       6     true    /if-/next x
15    1	     6       6       -     /for
16    2	     6       6     false   /if
17    3	     6       6       -     /echo 6
18    4	     6       7       -     /next x
19    1	     7       7       -     /for
20    2	     7       8     true    /if-/next (exit for/next)
21    3	     8       8       -     /echo 8
22    4	     8       8       -     /next (exit for/next again)
23 end.

Would produce the result (echo 2 4 6 8) as you programmed it to...

zanomo · Post by **zanomo** » Tue Aug 17, 2004 5:18 am

Sparr wrote:i was looping through bazaar results.

psudocode:
/for x 1 to bazaar.count
/if bazaar.itemx.name!=nameiwant /next x
do stuff
/next x

now that i know about this problem ive fixed the code as follows:
/for x 1 to bazaar.count
/if bazaar.itemx.name==nameiwant {
do stuff
}
/next x

Or to retain your logic flow using /goto:

Code: Select all

psudocode:
/for x 1 to bazaar.count
    /if bazaar.itemx.name!=nameiwant /goto :not_nameiwant
    do stuff
:not_nameiwant
/next x

Sparr · Post by **Sparr** » Tue Aug 17, 2004 5:22 am

on one part where i had more than two /next's i had to use the /goto solution, ended up abandoning /for completely on that one.

wassup · Post by **wassup** » Tue Aug 17, 2004 7:03 am

On a side note:

Code: Select all

Sub Main
   /declare x int local
   /for x 1 to 7
      /if (${x}%2) /next x
      /echo ${x}
   /next x
   /return

Isn't ${x}%2 considered a calculation?

I would have thought it would have to be:

Code: Select all

Sub Main
   /declare x int local
   /for x 1 to 7
      /if (${Math.Calc[${x}%2].Int}) /goto :Next
      /echo ${x}
      :Next
   /next x
/return

At least that is how I would have done it in a macro

Sparr · Post by **Sparr** » Tue Aug 17, 2004 7:05 am

yeah, you have to use math. i was just typing it off the top of my head :)

Caladine · Post by **Caladine** » Tue Aug 17, 2004 9:10 am

He's trying to use that first /next x like a continue; statement, which it can't actually be used as.

While it would be nice for the mq macro language to include a /break <variable name> and a /continue <variable name>, it's not particularly hard to use a /goto to get the same effect.