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Not just a gadget, but teletypes in general. (See e.g. https://en.wikipedia.org/wiki/Teletype_Model_33 https://en.wikipedia.org/wiki/Teletype_Model_33) You pre
by kps 10y ago
Not just a gadget, but teletypes in general. (See e.g. https://en.wikipedia.org/wiki/Teletype_Model_33 https://en.wikipedia.org/wiki/Teletype_Model_33) You press a key, it punches the code on paper tape. If there are already holes, the new holes get punched over top. All holes is the only thing that can be punched over anything else with a consistent result.
The intent was that, when reading tape, DEL is ignored, because it's a position that was punched over with DEL, i.e. deleted.
Also, when punching tape, a key will punch its holes and (naturally) advance to the next character position. For DEL, that means you erase the character under the cursor, and then the next character is under the cursor. That is, it's a ‘forward’ delete. (I think it was DEC's VT2x0 series terminals that screwed that up for everyone.)
- flyinghamster 10y agoAnd note also that Teletypes and paper tape were the rationale for the ultimate "you asked for it, you got it" text editor - TECO. The basic idea was, if you had a paper tape with typographical errors, you could feed that and a correction tape into TECO, and it would apply the corrections. It eventually morphed into an all-purpose editor; DEC's VTEDIT was a screen-oriented editor written in TECO macros, and Emacs was originally implemented in TECO as well. It's kind of appropriate that a typical TECO command line looks a lot like transmission line noise. :)
- kps 10y agoTECO = Tape Editor and COrrector
- mark-r 10y agoIt's still a forward delete in Windows.