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1 point by akkartik 3255 days ago | link | parent

Great! Then you should be able to drop the outer w/infile form and just say:

  (drain (readline stdin))


2 points by jsgrahamus 3255 days ago | link

  Error: "read-char: expects argument of type <input-port>; given #<procedure:current-input-port>"

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1 point by akkartik 3255 days ago | link

Sorry, typed that out on my phone without trying it out. You need parens around stdin.

  (drain (readline (stdin)))
Alternatively:

  (write:drain:readline:stdin)

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2 points by jsgrahamus 3255 days ago | link

  Unknown or expired link.
In the example above the READ X:5 or 15, allowed the read 5 or 15 seconds before timing out. I wonder if that is what we are seeing here.

Thanks for the help.

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2 points by jsgrahamus 3254 days ago | link

Here is a follow on problem as I'm going through the tutorial: obj does not work and the error message seems to access memory not involved with the obj.

  arc> (printlst alist)

  ARR(1)="PARSE    ; PARSE OUTPUT OF ^%RFIND INTO RSD/RTN/TAG"

  ARR(2)="         N ARR,FND,I,RSD,RTN,STOP,TXT"

  ARR(3)="         W !!,"PASTE""

  ARR(4)="         F  R !,X:15 Q:'$T  S ARR($I(ARR))=X"

  ARR(5)="         K RSDS"



  ""
  arc> (= codes (obj "Boston" 'bos "San Francisco" 'sfo "Paris" 'cdg))
  Error: "list-ref: contract violation\n  expected: exact-nonnegative-integer?\n  given: '(((codes (obj \"Boston\" (quote bos . nil) \"San Francisco\" (quote sfo . nil) \"Paris\" (quote cdg . nil) . nil) . nil) . nil))\n  argument position: 2nd\n  other arguments...:\n   '(\"\\nARR(1)=\\\"PARSE    ; PARSE OUTPUT OF ^%RFIND INTO RSD/RTN/TAG\\\"\" \"\\nARR(2)=\\\"         N ARR,FND,I,RSD,RTN,STOP,TXT\\\"\" \"\\nARR(3)=\\\"         W !!,\\\"PASTE\\\"\\\"\" \"\\nARR(4)=\\\"         F  R !,X:15 Q:'$T  S ARR($I(ARR))=X\\\"\" \"\\nARR(5)=\\\"         K RSDS\\..."
  arc>

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2 points by rocketnia 3254 days ago | link

Judging by that error message, it looks like the variable "=" or one of its dependencies might have been reassigned somewhere along the line. The second argument in that error message indicates that = is getting hold of your read-in data somehow, so it might be something you've defined for processing this data.

The dependencies of = include expand=list, expand=, map, pair, and setforms (among others), so if any of these has been overwritten, it might do something like what you're seeing.

By the way, I think if you're not using Anarki, there's a known bug in (readline ...) where it will spuriously combine each empty line with the following line (https://sites.google.com/site/arclanguagewiki/arc-3_1/known-...). Maybe this could explain the extra \n you're getting.

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2 points by jsgrahamus 3253 days ago | link

Thank you.

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2 points by jsgrahamus 3254 days ago | link

Followon #2

Stopped arc and restarted it and had no problems with obj

How prone is arc to memory problems?

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1 point by akkartik 3254 days ago | link

Hmm, not sure what happened. Not sure what you mean by memory problems, but I've never seen flakiness in a session this short. Perhaps something in your earlier session was accidentally a control character or something. Keep an eye out for it and I will too.

Here's a full session I tried out on linux:

  $ arc
  arc> (def printlst (thelist) (if (is thelist nil) (prn "") (do (prn (car thelist)) (printlst (cdr thelist)))))
  #<procedure: printlst>
  arc> (def readit () (drain (readline (stdin))))
  #<procedure: readit>
  arc> (= alist (readit))
  ARR(1)="PARSE    ; PARSE OUTPUT OF ^%RFIND INTO RSD/RTN/TAG"

  ARR(2)="         N ARR,FND,I,RSD,RTN,STOP,TXT"

  ARR(3)="         W !!,"PASTE""

  ARR(4)="         F  R !,X:15 Q:'$T  S ARR($I(ARR))=X"

  ARR(5)="         K RSDS"
  ("" "ARR(1)=\"PARSE    ; PARSE OUTPUT OF ^%RFIND INTO RSD/RTN/TAG\"" "" "ARR(2)=\"         N ARR,FND,I,RSD,RTN,STOP,TXT\"" "" "ARR(3)=\"         W !!,\"PASTE\"\"" "" "ARR(4)=\"         F  R !,X:15 Q:'$T  S ARR($I(ARR))=X\"" "" "ARR(5)=\"         K RSDS\"")
  arc> (printlst alist)

  ARR(1)="PARSE    ; PARSE OUTPUT OF ^%RFIND INTO RSD/RTN/TAG"

  ARR(2)="         N ARR,FND,I,RSD,RTN,STOP,TXT"

  ARR(3)="         W !!,"PASTE""

  ARR(4)="         F  R !,X:15 Q:'$T  S ARR($I(ARR))=X"

  ARR(5)="         K RSDS"

  ""
  arc> (= codes (obj "Boston" 'bos "San Francisco" 'sfo "Paris" 'cdg))
  #hash(("Boston" . bos) ("Paris" . cdg) ("San Francisco" . sfo))
  arc>

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2 points by jsgrahamus 3253 days ago | link

Thanks. Not sure what happened.

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1 point by akkartik 3254 days ago | link

I don't follow. You got this message when you tried my code snippet? That seems really strange!

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2 points by jsgrahamus 3254 days ago | link

Perhaps it was because I was using tryarc.org?

So I tried again with arc running on Racket under Linux. Here's what I found:

  arc> (def readit () (drain (readline (stdin))))
  #<procedure: readit>
  arc> (readit)
  ARR(1)="PARSE    ; PARSE OUTPUT OF ^%RFIND INTO RSD/RTN/TAG"

  ARR(2)="         N ARR,FND,I,RSD,RTN,STOP,TXT"

  ARR(3)="         W !!,"PASTE""

  ARR(4)="         F  R !,X:15 Q:'$T  S ARR($I(ARR))=X"

  ARR(5)="         K RSDS"

  ("\nARR(1)=\"PARSE    ; PARSE OUTPUT OF ^%RFIND INTO RSD/RTN/TAG\"" "\nARR(2)=\"         N ARR,FND,I,RSD,RTN,STOP,TXT\"" "\nARR(3)=\"         W !!,\"PASTE\"\"" "\nARR(4)=\"         F  R !,X:15 Q:'$T  S ARR($I(ARR))=X\"" "\nARR(5)=\"         K RSDS\"" "\n")
  arc> (= alist (readit))
  ARR(1)="PARSE    ; PARSE OUTPUT OF ^%RFIND INTO RSD/RTN/TAG"

  ARR(2)="         N ARR,FND,I,RSD,RTN,STOP,TXT"

  ARR(3)="         W !!,"PASTE""

  ARR(4)="         F  R !,X:15 Q:'$T  S ARR($I(ARR))=X"

  ARR(5)="         K RSDS"

  ("\nARR(1)=\"PARSE    ; PARSE OUTPUT OF ^%RFIND INTO RSD/RTN/TAG\"" "\nARR(2)=\"         N ARR,FND,I,RSD,RTN,STOP,TXT\"" "\nARR(3)=\"         W !!,\"PASTE\"\"" "\nARR(4)=\"         F  R !,X:15 Q:'$T  S ARR($I(ARR))=X\"" "\nARR(5)=\"         K RSDS\"" "\n")
  arc> alist
  ("\nARR(1)=\"PARSE    ; PARSE OUTPUT OF ^%RFIND INTO RSD/RTN/TAG\"" "\nARR(2)=\"         N ARR,FND,I,RSD,RTN,STOP,TXT\"" "\nARR(3)=\"         W !!,\"PASTE\"\"" "\nARR(4)=\"         F  R !,X:15 Q:'$T  S ARR($I(ARR))=X\"" "\nARR(5)=\"         K RSDS\"" "\n")
  arc> (len alist)
  6
  arc> (def printlst (thelist) (if (is thelist nil) (prn "") (do (prn (car thelist)) (printlst (cdr thelist)))))
  #<procedure: printlst>
  arc> (printlst alist)

  ARR(1)="PARSE    ; PARSE OUTPUT OF ^%RFIND INTO RSD/RTN/TAG"

  ARR(2)="         N ARR,FND,I,RSD,RTN,STOP,TXT"

  ARR(3)="         W !!,"PASTE""

  ARR(4)="         F  R !,X:15 Q:'$T  S ARR($I(ARR))=X"

  ARR(5)="         K RSDS"



  ""
  arc>
I think the issue with the \n is sending data between Windows and Linux.

I did have to key in Ctrl-D twice to actually get the function to finish reading. Is there a better way to do this?

Thanks for all of the help with this.

Steve

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2 points by akkartik 3254 days ago | link

Ah, yes tryarc would explain it.

By "the issue with the \n" do you mean how each line has a \n at the start? How is this sending data between Windows and Linux, can you elaborate?

Yes, it's weird that you had to hit ctrl-d twice. Thanks. I'll try your example on windows later today.

Both these issues aren't happening for me on linux, so it seems likely to be a windows issue.

Edit: Hmm, I do see a leading empty list at the start when reading stdin:

  arc> (readit)
  abc
  def
  ("" "abc" "def")
It looks like stdin doesn't behave quite like a regular file handle.. Thanks for the report! I'll investigate why this is happening.

Edit 2: The trouble seems to be that the first call to 'readline' receives the 'enter' you hit to type in the command.

  arc> (readline (stdin))
  ""
  arc>
I think your examples might work if you put the code into a .arc file and try to run it like my original example..

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2 points by jsgrahamus 3253 days ago | link

This probably seems weird, but I capture the data on a Windows system, then e-mail the data to a Linux system which is where arc resides. I assume Windows and Linux have different line endings.

Perhaps I need to check out the community version of arc?

Has anyone figured out a way to compile an arc routine? I saw an earlier thread on it, but no resolution.

Thanks for everything.

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