Hello 

Can someone tell me why I get different results for n = 0
with these two variants?

find-nth0: func [
        "Returns the series after the Nth occurrence of value or none."
        series [series!]
        value
        N [integer!]
        /local pos
] [
        parse series [n [thru value]  pos: to end] 
        pos
]

find-nth1: func [
        "Returns the series after the Nth occurrence of value or none."
        series [series!]
        value
        N [integer!]
        /local pos
] [
        parse series [n thru value  pos: to end] 
        pos
]

>> find-nth1 "0**3*4" "*" 0
== none
>> find-nth0 "0**3*4" "*" 0
== "0**3*4"
>>

Or with other questions;
why is zero times [..] true
and zero times .. false?

Other n's give the same result

>> find-nth1 "0**3*4" "*" 3
== "4"
>> find-nth0 "0**3*4" "*" 3
== "4"

AR



>
> 
> Andreas Bolka napsal(a):
> 
> >Wednesday, January 19, 2005, 12:23:28 PM, Gabriele wrote:
> >
> >  
> >
> >>so you'd need to check PARSE's result and return NONE if it didn't
> >>match.
> >>    
> >>
> >
> >and so that this exercise is not left to the reader:
> >
> >    find-nth: func [
> >        "Returns the series at occurrence N of value or none."
> >        series [series!]
> >        value
> >        n [integer!]
> >        /local pos
> >    ] [
> >        either parse series [n [to value pos: value] to end] [pos] [none]
> >    ]
> >
> >  
> >
> I sent my correction
> 
>   find-nth: func [
>       "Returns the series at occurrence N of value or none."
>       series [series!]
>       value
>       n [integer!]
>       /local pos
>   ] [
>       if parse series [n [to value pos: value] to end] [pos]
>   ]
> 
> immediately, but it didn't make it to the list yet :-(
> 
> 
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