This is brilliant and elegant. It's quite satisfying to have ways to have older computers communicate with the rest of the world. Thanks, Cameron, for preserving and extending this work from and history of John Iannetta.
The BASIC interpreter parses numerical values from text each time a token gets executed. It converts that into a float and, in the case of POKE, then into an integer. Using the dot without the implicit leading zero, there's no need to convert a "0” (48 in decimal) into a zero and, possibly, a multiplication by 10 of previously parsed digits, in this case the starting zero value.
Maybe, but it is not known that he did for that particular reason.
The sales assistants in department stores on the other hand... different story.
In the 80s stores often had home computers for display and for customers to try them out. Much like they have tablets and phones on display now. Kids being kids used to play pranks with these machines and one way to hang a Commodore 64 was POKE 1,0 (or POKE 1,.). The store employees hated it because they had to come and reset the machines all the time.
For me POKE 1,0 will always be burned into my mind as a dangerous frightening command, hence the " Oh, nooo".
I do not have any information if Edsger Dijstra held similar feelings and whether they contributed to his hate for BASIC.
Sorry. I was joking. Dijkstra’s criticism wasn’t as much for the syntax.
I would, however, prefer “POKE X” as a shorthand for “POKE X, 0”, but this might as well be a bug of the parser rather than an intended feature. Code had to be very compact back then.
If it’s one-way, it’s just a “mo”. The “dem” part will only be on the other side.
This is brilliant and elegant. It's quite satisfying to have ways to have older computers communicate with the rest of the world. Thanks, Cameron, for preserving and extending this work from and history of John Iannetta.
Thanks, John! It was one of my favourite posts he made. It deserved a second life, and usefully, too.
Wow, the "POKE i,." notation does work. Are there any advantages to doing so instead of typing zero for the value?
The BASIC interpreter parses numerical values from text each time a token gets executed. It converts that into a float and, in the case of POKE, then into an integer. Using the dot without the implicit leading zero, there's no need to convert a "0” (48 in decimal) into a zero and, possibly, a multiplication by 10 of previously parsed digits, in this case the starting zero value.
For a moment I saw
POKE 1,.
and thought "Oh, Noooo";-)
This is why Edsger Dijkstra hated BASIC so much…
Maybe, but it is not known that he did for that particular reason. The sales assistants in department stores on the other hand... different story.
In the 80s stores often had home computers for display and for customers to try them out. Much like they have tablets and phones on display now. Kids being kids used to play pranks with these machines and one way to hang a Commodore 64 was POKE 1,0 (or POKE 1,.). The store employees hated it because they had to come and reset the machines all the time.
For me POKE 1,0 will always be burned into my mind as a dangerous frightening command, hence the " Oh, nooo". I do not have any information if Edsger Dijstra held similar feelings and whether they contributed to his hate for BASIC.
Sorry. I was joking. Dijkstra’s criticism wasn’t as much for the syntax.
I would, however, prefer “POKE X” as a shorthand for “POKE X, 0”, but this might as well be a bug of the parser rather than an intended feature. Code had to be very compact back then.
Dijkstra did much for computing, but an entire generation of developers inspired by and initially taught by BASIC did a LOT more.
Me included, BTW. BASIC was the first language I learned (second if we count programming a TI-55 calculator as first).