On 22/02/14 23:49, J. Landman Gay wrote:
On 2/22/14, 1:35 PM, Richmond wrote:
Sorry: Neanderthal question time:
I cannot see anything about charsToSkip in the inbuilt (i.e. in the IDE)
documentation (6.6. dp1).
It's the third parameter in the "offset" function. See "offset" in the
dictionary.
I set up a boring little stack with a fld "fORIGIN" conatinong "The
quick brown fox jumps over the lazy dog"
and that was jolly nice,
then I set up another fld called "fREZ"
and a button with this script:
on mouseUp
put empty into fld "fREZ"
put fld "fORIGIN" into ORIGIN
put offset("o",ORIGIN) & ", " after fld "fREZ"
put offset("o",ORIGIN) & ", " after fld "fREZ"
put offset("o",ORIGIN) & ", " after fld "fREZ"
end mouseUp
in the hope I would get something like "13, 18, 27," in fld "fREZ"
but all I got was "13, 13, 13"
so I really cannot see what the utility of 'offset' is at all.
Oh ye of little faith. That's what we've been talking about; every
instance of "offset" starts at the beginning of the string unless you
include the number of characters to skip as the third parameter.
This is a much faster way to get all instances of an offset in a block
of text, exactly parallel to the differences between "repeat with x"
and "repeat for each". Like "for each," offset will read from the
current marked location rather than counting from the top during each
iteration, provided you include the third parameter. Your example
handler doesn't use the parameter, so of course you're getting the
same offset repeatedly.
If there is a third parameter, then offset will start counting from
that point, and return the number of characters from that location in
the text to the next instance of the character. It's up to you to add
that number to the current "skip" location in order to keep the marker
moving along.
This should do what you want:
function getAllOffsets pData,pChar -- find all instances of a char
put 0 into tSkip -- start at beginning
repeat
put offset(pChar,pData,tSkip) into tNextOffset -- chars since skip
point
if tNextOffset = 0 then exit repeat -- no more found
add tNextOffset to tSkip -- move the marker
put tSkip & comma after tRes -- store it
end repeat
return tRes
end getAllOffsets
This should be much faster than your "repeat" example (which counts
characters from the top during each iteration) or a version that
deletes characters from the original data. Try some comparison timings
with a very large block of text.
You AVOIDED commenting on this:
/I made another button with this script:
//
// on mouseUp
// put empty into fld "fREZ"
// put 1 into INDEKS
// repeat until char INDEKS of fld "fORIGIN" is empty
// if char INDEKS of fld "fORIGIN" is "o" then
// put INDEKS & ", " after fld "fREZ"
// else
// --do nix
// end if
// put (INDEKS + 1) into INDEKS
// end repeat
// end mouseUp
//
// and that returned "13, 18, 27, 42"
//
// a whole lot more useful./
No need to work out how far to hop!
Richmond.
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