World: r3wp

I dont understand how this prevents the sort of problems I might 
get using global variables?  I was expecting to have to define the 
object inside the function to keep all the variables local to the 
function.

I am thinking that if I take care with these things I will be able 
to reuse fragments of code in lots of projects without worrying that 
I have used the same global variable in two places that conflict.

no you must use the /local switch to do that.

func [arg1 arg2 /local lc1 lc2 ...][body...]

Paul, how does that relate to using objects please?

Only the things you define in a function as local are local.

Each object has its own context. All variables in the object are 
local to the object's context. Only the object "variable" would be 
in the global context:

>> a: 1

== 1

>> obj: make object! [
[    a: "one"
[    b: "two"
[    c: "three"

[    ]
>> a
== 1
>> obj/a
 
== "one"

>> b

** Script Error: b has no value
** Near: b

>> obj/b
 
== "two"

Hi, I have been puzzeling over this all evening & would love a few 
tips please.

I am trying to write a single parse rule that will extract the first 
number before the "/" in each case, but my logic must be faulty I 
think.

digit: charset [#"0" - #"9"]
data1: {random 10/2}
data2: {2/33-35,2/48}

parse/all data1 [ some [[h: 1 2 digit :h copy result to "/" thru 
end] | skip]]
result

parse/all data2 [ some [[h: 1 2 digit :h copy result to "/" thru 
end] | skip]]
result

something like this?
digit: charset [#"0" - #"9"]
rest: complement digit
data1: {random 10/2}
data2: {2/33-35,2/48}


parse/all data1 [any [copy x some digit #"/" (probe x) | some digit 
| some rest]]

parse/all data2 [any [copy x some digit #"/" (probe x) | some digit 
| some rest]]

PeterWood, thanks for your example. I think I understand too little 
about objects to use them to any benifit yet, I expect it will slowly 
get clearer.

or 

parse/all data1 [any [copy x some digit opt [#"/" (probe x)] | skip]]

Thanks Oldes, that looks good. I didnt know I could use compliment 
in a parse like that either. I must have been doing it wrong when 
I tried as I kept getting errors. 

Thanks Steeve, I must go & study more about opt too now.   I very 
much appreciate you clever guys coming in this group to help me with 
my simple questions. I am begining to get a bit more productive with 
some of the things I am trying to do, although I am still very much 
a beginner in most areas. Thanks.

I just don't "get" Parsing..  I dont understand the syntax & every 
new thing I try takes hours before I chance upon the right syntax. 
 There are so many tutorials & examples that I dont really know which 
one to concentrate my time reading.  When i use OR (|) I get paticularly 
confused as it dosnt seem to evaluate the expressions in order in 
every case.

you mean parsing with charsets or the "normal" parsing?

normal I think

Like it took me an hour to work out how to modify Steeve's example 
to only output the first occurance of the match.

aha, that is easier to learn .. I also don't the advanced parsing 
that oldes gave you example, and I wrote a couple of finished programs 
that used "normal" parsing as a main featurea

start with easy examples and go forward from that

Trouble is that the easy examples dont produce the results I need 
for processing my data :-(

I have spent about 6 hours so far trying to convert this sort of 
format {random 2/2,2/4-6,2/33-37} to module: 2 port: [2 4 5 6 33 
34 35 36 37]  So far even with lots of help I have only managed to 
extract the module number & the ranges, but not the last one because 
there is no comma after it.

I suppose I could add a comma to the end of the string then I would 
be able to use it as a marker.

sometimes an easier solution is possible if you do it in more parse 
runs

or if only comma is the problem slap it at the end and be done with 
it

yes, for something like that, I would do some simple splitting to 
get the numbers isolated.

... from where do you parse 5 out... is that supose NUM-NUM suppose 
to be ranges?

so I will add a comma to the end, then parse data [any [ some digit 
#"/" copy result #"," (insert results result) | skip]]

If it is I wouldn't call that a parse problem, ... remember you have 
to divide and conquer the problems , and that looks like a compound 
problem which parsing is not the big part of.. you just need regular 
"split" method

some are ranges & some are single ports

what does 2 mean in 2/x-y ?

the 2 is a module number on a Cisco catos switch

I qould 1) split on comma to get list of entities  2) for each entity 
if it's a single num append it to block, else split again and append 
 whole range to the block

the port information is stored in a form like
set port disable 2/2,2/4,2/6-8
set port disable 3/1-5,3/7
Then the same sort of thing for the names given to the ports.

I want to extract it all into a standard format for analysis & comparison 
of IOS based information (done the IOS stuff ok)

a: [...]
some-a-with-comma: [a any ["," a]]

CIsco operating systems are IOS or CATOS on switches and output formats 
are very different.

mhinson: the above {copy result #","} does not look intended to me

ah, do I need a copy result to perhaps?

if {copy result to ...} is what you want then I understand why you 
are having trouble with the END

not-comma: complement charset ","
copy result any [not-comma | skip]

sorry, just copy result not-comma

I think the advice to break the problem down and use more than one 
parse statement is good advice. Let's see how we can do that.


I'll go through how I would approach the problem step by step. Sorry 
that I'll be squashing things on to one line but AltME paste doesn't 
work well on Mac.

:-)

I usually try to take a few small steps rather than try to get the 
answer straight away.

The test data:

>> inp:  {random 2/2,2/4-6,2/33-37}

== "random 2/2,2/4-6,2/33-37"

random is sometimes a word & sometimes a number between 1 & 1000

We'll need to look for digits so :

> digit: charset [#"0" - #"9"]                   
  
== make bitset! #{

000000000000FF03000000000000000000000000000000000000000000000000

}

Does random ever have the sequence 2/number in it?

no

specific words (not many of them) on numeric alone

So what we need to look for are the patterns 2/number and 2/number-number.

on=or

or 3/number...etc or 4/ or 12/