4 ms·

What I always admired about the ZX-Spectrum's Basic was that it skipped the entire idea of a lexer, because, well, the keyboard let you input tokens directly.

jacobush 6y ago
Which tied into how they could make the keyboard cheaper, remember the rubber keys? :-)
Lerc 6y ago
I think it was closer to the other way around. The keyboard let you input tokens because it didn't have a lexer. I suspect this is more due to the memory cost of storing a literal line of code more than the ROM or CPU cost of a lexer. Going back to the ZX-80 storing even the current line being typed as characters was probably a burden.
- tachyonbeam 6y ago
  AFAIK the keyboard was also just very cheap and a pain to type on.
  - webreac 6y ago
    I don't remember complaining about keyboard. The only issue was loosing memory because the memory expansion (16ko) had bad contacts.
    - thom 6y ago
      Ha, my dad tells me we had a strict rule of no running in the house while he was working on the Spectrum for this exact reason.
  - JasonFruit 6y ago
    The keyboard was a disaster. My dad had an old teletype keyboard and adapted that to it when the original membrane died. I was pretty impressed.
- Someone 6y ago
  That can’t be it. The Basic interpreter could run the lexer on each line the user typed and store the tokens. You would lose the ability to print lines exactly the way the user typed them, but that isn’t a big blocker for the technology of the time. Alternatively, the Basic interpreter could store each line as a combination of tokens and characters. Commodore Basic did that (https://www.masswerk.at/nowgobang/2020/commodore-basic-renumber https://www.masswerk.at/nowgobang/2020/commodore-basic-renum...). I also think none of the microcomputer Basics stored keywords as ascii strings. It would both slow down the interpreter and use more memory.
  - edw 6y ago
    I can confirm that AppleSoft ][ BASIC stored its programs in memory in tokenized form. On another note, I went ahead and wrote a code emitter, because I couldn't wait for part three (though I noticed it's in the GitHub repo). Once you get this compiler up and running the sane thing to do is write a Makefile so you can treat Teeny as a first-class programming language. Just add a Makefile with the following: %.c : %.tiny <TAB>python3 ./teenytiny.py $< > $@ And you'll be able to type `make hello` and have hello.tiny compiled to hello.c compiled to hello automagically. I can never pass up an opportunity to remind people that Make is wonderful.
stevekemp 6y ago
I wrote a simple BASIC interpreter inspired by the Sinclair, over here https://github.com/skx/gobasic https://github.com/skx/gobasic

jacobush 6y ago

Which tied into how they could make the keyboard cheaper, remember the rubber keys? :-)

Lerc 6y ago

I think it was closer to the other way around. The keyboard let you input tokens because it didn't have a lexer. I suspect this is more due to the memory cost of storing a literal line of code more than the ROM or CPU cost of a lexer. Going back to the ZX-80 storing even the current line being typed as characters was probably a burden.

tachyonbeam 6y ago
AFAIK the keyboard was also just very cheap and a pain to type on.
- webreac 6y ago
  I don't remember complaining about keyboard. The only issue was loosing memory because the memory expansion (16ko) had bad contacts.
  - thom 6y ago
    Ha, my dad tells me we had a strict rule of no running in the house while he was working on the Spectrum for this exact reason.
- JasonFruit 6y ago
  The keyboard was a disaster. My dad had an old teletype keyboard and adapted that to it when the original membrane died. I was pretty impressed.
Someone 6y ago
That can’t be it. The Basic interpreter could run the lexer on each line the user typed and store the tokens. You would lose the ability to print lines exactly the way the user typed them, but that isn’t a big blocker for the technology of the time. Alternatively, the Basic interpreter could store each line as a combination of tokens and characters. Commodore Basic did that (https://www.masswerk.at/nowgobang/2020/commodore-basic-renumber https://www.masswerk.at/nowgobang/2020/commodore-basic-renum...). I also think none of the microcomputer Basics stored keywords as ascii strings. It would both slow down the interpreter and use more memory.
- edw 6y ago
  I can confirm that AppleSoft ][ BASIC stored its programs in memory in tokenized form. On another note, I went ahead and wrote a code emitter, because I couldn't wait for part three (though I noticed it's in the GitHub repo). Once you get this compiler up and running the sane thing to do is write a Makefile so you can treat Teeny as a first-class programming language. Just add a Makefile with the following: %.c : %.tiny <TAB>python3 ./teenytiny.py $< > $@ And you'll be able to type `make hello` and have hello.tiny compiled to hello.c compiled to hello automagically. I can never pass up an opportunity to remind people that Make is wonderful.

stevekemp 6y ago

I wrote a simple BASIC interpreter inspired by the Sinclair, over here https://github.com/skx/gobasic https://github.com/skx/gobasic