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I'm trying to learn Smalltalk and so I'm doing the "Squeak by Example" tutorial. I have to write a method in the system browser with a vertical arrow which points up at the beginning of the code. Is there a Unicode sign or something like this, which I could use in Windows?

Thanks in advance (I know, it's a very simple question, but I don't get the clue)! :)

Janus
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2 Answers2

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Vertical arrow is ^ on your keyboard.

Squeak was namely an Apple sponsored project and from Mac keyboard comes a vertical arrow. On non-Mac computers a ^ is an equal replacement.

Janko Mivšek
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    Older version of Squeak also had a font that rendered the caret as an up arrow. But that probably caused more trouble than it's worth. – Alex Jasmin Oct 19 '11 at 11:06
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    You may also come across ← for assignment. It was a special rendering of the _ (underscore) character but := is now recommended. – Alex Jasmin Oct 19 '11 at 11:14
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    Also was there really such a key on the Mac keyboard? I always though that was an early PARC thing that stuck. But I may be wrong. – Alex Jasmin Oct 19 '11 at 11:31
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    The up arrow predates the existence of Macs: it comes from Smalltalk, not Squeak (just look in the Blue Book). – Frank Shearar Oct 19 '11 at 12:09
  • @Frank Yeah I didn't think it was a Mac or Squeak thing. It'd be nice if someone more informed could post an answer. I wonder if you could type these arrow characters on the Alto keyboard for instance. – Alex Jasmin Oct 19 '11 at 20:06
  • Dan Ingalls counts as informed, I reckon :) "The Smalltalk-76 Programming System Design and Implementation" uses up- and left-arrows. The "Smalltalk-72 Instruction Manual" also uses up- and left-arrows. (Notably, both use a hollow up-arrow - think an equals sign on its side and topped with a ^.) – Frank Shearar Oct 19 '11 at 21:01
  • @Frank Interesting so it predates Smalltalk-80. I also found a [picture of the Alto](http://upload.wikimedia.org/wikipedia/commons/8/8b/Xerox_Alto.jpg) on Wikipedia and it has a key with the two arrows on it! I imagine you'd press shift to get the the uparrow. Interestingly there are no cursor keys. Frank since you seem to have researched that a bit could you post a an answer that get this right? Or Janko could you edit out the *Mac keyboard* bit? – Alex Jasmin Oct 19 '11 at 21:30
  • The ASR-33, on which I started to program had an up-arrow. There was no caret then on many machins (on any?). See http://www.pdp8.net/asr33/pics/kbd_top.shtml?large (you will also find the back-arrow there...) – blabla999 Jun 04 '12 at 21:57
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This answer serves as a historical note on the up arrow. "The Smalltalk-76 Programming System Design and Implementation" uses up- and left-arrows. The "Smalltalk-72 Instruction Manual" also uses up- and left-arrows. (Notably, both use a hollow up-arrow - think an equals sign on its side and topped with a ^.)

Frank Shearar
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