Because LC can't do two things at once.

[Peter Haworth]

I like what you said about "not speaking Regex".  I think that's the
biggest problem people have with Regex: it's a language and if you don't
know the syntax rules of any language, it doesn't make sense.  Good analogy.

Here's the regex for extracting what you want from the Mac output:

'(\w*)

Translated into English, it means "Look for a ' character and return all
characters after it in the range A-Z, or a-z, or 0-9 until you come across
a character that is not in that range"

Armed with that, the single statement below gets you "AC" or "Battery"

matchText(tSource,"'(\w*)",tPowerSource)

I'd be happy to supply the regex for the other platforms if someone
supplies the format of the output.

On Sat Feb 21 2015 at 8:03:50 AM Peter M. Brigham <pmbrig at gmail.com> wrote:

> On Feb 21, 2015, at 2:59 AM, Richard Gaskin wrote:
>
> > Peter M. Brigham wrote:
> >
> >> Just out of curiosity, how *would* you do this via shell call or
> >> the equivalent on a Windows laptop?
> >
> > Good question.
> >
> > Thanks to the beautiful simplicity of the Linux /proc directory I was
> able to find:
> >
> > cat /proc/acpi/battery/BAT1/state
> >
> > The "charging state" field there will contain "charging" or
> "discharging".
> >
> > Now if we can turn up a Win command line solution I'll write a handler
> for this that'll make it convenient to get this info on all three platforms.
>
> That was my thought too. I was waiting for more info, but I started with
> the handler(s) below. I don't speak Regex so I converted that line to use a
> native LC function instead, getNestedItem() -- from your function posted
> here several months ago, Richard, called nDepth(). I use this so often that
> its now an essential part of my library. It's much more comprehensible to
> me than Regex, though it can't do everything Regex can. So the quantity of
> code below is really mostly utility handlers and the basic
> getMacPowerSource() is very compact, as was the original.
>
> I'll leave the other platforms to you, Richard. (If you use Regex, I'll
> translate it!   :-)  )
>
> > Martin, thanks for handling the Mac side - nice work.
>
> Yes, thanks!
>
> -- Peter
>
> Peter M. Brigham
> pmbrig at gmail.com
> http://home.comcast.net/~pmbrig
>
> -------
>
> function getMacPowerSource
>   -- returns the current power source for a Mac
>   --    "AC" or "Battery"
>   -- requires getNestedItem() getItem(), getDelimiters()
>   put shell ("pmset -g batt") into tSource
>   -- returns something like:
>   --    Currently drawing from 'AC Power'
>   --    -InternalBattery-0      99%; finishing charge; 0:00 remaining
>   return getNestedItem(tSource,2,"'",1,space)
> end getMacPowerSource
>
> function getNestedItem
>   -- allows specifying different delimiters to extract nested chunks
>   --    getNestedItem(tData,index1,delim1,index2,delim2,...)
>   -- eg, put "aaa,bbb,ccc*ddd*eee*fff,ggg,hhh" into tData
>   --     put getNestedItem(tData,3,comma,2,"*") -> "ddd"
>   --        *-delim item 2 of comma-delim item 3
>   -- specified delimiters can be strings, not just single characters,
>   -- so the following extracts the top-level domain name from a URL:
>   --    put "http://www.nytimes.com/pages/science/index.html/" into tURL
>   --    put getNestedItem(tURL,2,"://",1,"/") -> www.nytimes.com
>   -- based on a function by Richard Gaskin, use-LC list, originally named
> nDepth()
>   --    debugged by members of the use-LC list,
>   --    expanded by Peter M. Brigham, pmbrig at gmail.com
>   -- the result is a very versatile tool for extracting strings from any
> text
>   --    with a known structure
>   -- requires getItem(), getDelimiters()
>
>   put paramcount() into prmCount
>   if prmCount mod 2 <> 1 or prmCount = 1 then
>      return "getNestedItem(): error in parameters."
>   end if
>   put param(1) into workingString
>   repeat with i = 2 to prmCount-1 step 2
>      if workingString = empty then return empty
>      put param(i) into pItemNbr
>      put param(i+1) into tDelim
>      put getItem(workingString,pItemNbr,tDelim) into workingString
>   end repeat
>   return workingString
> end getNestedItem
>
> function getItem pList, pIndex, pDelim
>   -- returns item # pIndex of pList, given itemdelimiter = pDelim
>   -- could just "get item pIndex of pList" in the calling handler but
>   --    then have to set and restore the itemDelimiter, so this is less
> hassle
>   -- defaults to pDelim = tab
>   -- allows pDelim to be a string of characters
>   --    so you could do this:
>   --    getItem("a//b//c//d//e//f",4,"//") -> d
>   -- also allows pIndex to be a range, eg "3-5"
>   --    in that case enclose the range in quotes
>   -- by Peter M. Brigham, pmbrig at gmail.com — freeware
>   -- requires getDelimiters()
>
>   if pDelim = empty then put tab into pDelim
>   if len(pDelim) > 1 then
>      put getDelimiters(pList) into tempDel
>      if tempDel begins with "Error" then
>         return "Error in getDelimiters()"
>      end if
>   else
>      put pDelim into tempDel
>   end if
>   replace pDelim with tempDel in pList
>   set the itemdelimiter to tempDel
>   put offset("-",pIndex) into dashPos
>   if dashPos > 1 then
>      -- don't catch if pIndex is something like -1, -2, etc
>      put char 1 to dashPos-1 of pIndex into tStart
>      put char dashPos+1 to -1 of pIndex into tEnd
>      put item tStart to tEnd of pList into theItem
>      replace tempDel with pDelim in theItem
>   else
>      put item pIndex of pList into theItem
>   end if
>   return theItem
> end getItem
>
> function getDelimiters pText, nbr
>   -- returns a cr-delimited list of <nbr> characters
>   --    not found in the variable pText
>   -- use for delimiters for, eg, parsing text files, loading arrays, etc.
>   -- usage: put getDelimiters(pText,2) into tDelims
>   --        if tDelims begins with "Error" then exit to top -- or whatever
>   --        put line 1 of tDelims into lineDivider
>   --        put line 2 of tDelims into itemDivider
>   --             etc.
>   -- by Peter M. Brigham, pmbrig at gmail.com — freeware
>
>   if pText = empty then return "Error: no text specified."
>   if nbr = empty then put 1 into nbr -- default 1 delimiter
>   put "2,3,4,5,6,7,8,16,17,18,19,20,21,22,23,24,25,26" into baseList
>   -- low ASCII values, excluding CR, LF, tab, etc.
>   put the number of items of baseList into maxNbr
>   if nbr > maxNbr then return "Error: max" && maxNbr && "delimiters."
>   repeat with tCount = 1 to nbr
>      put true into failed
>      repeat with i = 1 to the number of items of baseList
>         put item i of baseList into testNbr
>         put numtochar(testNbr) into testChar
>         if testChar is not in pText then
>            -- found one, store and get next delim
>            put false into failed
>            put testChar into line tCount of delimList
>            exit repeat
>         end if
>      end repeat
>      if failed then
>         if tCount = 0 then
>            return "Error: cannot get any delimiters."
>         else if tCount = 1 then
>            return "Error: can only get one delimiter."
>         else
>            return "Error: can only get" && tCount && "delimiters."
>         end if
>      end if
>      delete item i of baseList
>   end repeat
>   return delimList
> end getDelimiters
>
> -------
>
>
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