4 ms·

Lisp syntax is (<operator> <args...>) with a few special forms (def, if, cond etc.). This is really easy to understand and allows the user to go straight forwar

by klrr 13y ago

Lisp syntax is (<operator> <args...>) with a few special forms (def, if, cond etc.). This is really easy to understand and allows the user to go straight forward and learn about the semantics and general programming practice immediately.

skrishnamurthi 13y ago
That same regularity also means there are few guideposts as a student programs, and this makes it much harder to recover from mistakes. We've looked at a lot data on this (and have taught Racket at every level for decades).
- ufo 13y ago
  This reminds me a bit about a similar problem in Haskell. The syntax is very whitespacey so lots of things that would usually be syntax errors in other languages end up being interpreted as invalid function applications, leading to complex type-errors.
  - skrishnamurthi 13y ago
    Absolutely. For instance, if you leave off an argument in a recursive call, Haskell will quietly think you meant to curry the called function, which can manifest itself as a type error in some entirely different place.
- chongli 13y ago
  If you need guideposts, use an editor with paredit support and rainbow delimiters. This makes Lisp feel far more intuitive and tree-like than normal.
  - skrishnamurthi 13y ago
    You seem to be under the impression I haven't programmed in Lispy languages. And our data are from students using DrRacket, which very much has paredit support. These are just inconvenient truths.
    - chongli 13y ago
      DrRacket is a very big language. How does it compare with using a much smaller language such as the Scheme used in SICP?
      - samth 13y ago
        DrRacket is an IDE that supports many languages. The curricula that Shriram has used at Brown, and that others have used in many other places uses a sequence of smaller languages designed for teaching.
      - skrishnamurthi 13y ago
        Our studies were on students using Beginning Student Language, the smallest of the languages built into DrRacket. It is much smaller than the Scheme used in SICP.

by klrr 13y ago

skrishnamurthi 13y ago

That same regularity also means there are few guideposts as a student programs, and this makes it much harder to recover from mistakes. We've looked at a lot data on this (and have taught Racket at every level for decades).

ufo 13y ago
This reminds me a bit about a similar problem in Haskell. The syntax is very whitespacey so lots of things that would usually be syntax errors in other languages end up being interpreted as invalid function applications, leading to complex type-errors.
- skrishnamurthi 13y ago
  Absolutely. For instance, if you leave off an argument in a recursive call, Haskell will quietly think you meant to curry the called function, which can manifest itself as a type error in some entirely different place.
chongli 13y ago
If you need guideposts, use an editor with paredit support and rainbow delimiters. This makes Lisp feel far more intuitive and tree-like than normal.
- skrishnamurthi 13y ago
  You seem to be under the impression I haven't programmed in Lispy languages. And our data are from students using DrRacket, which very much has paredit support. These are just inconvenient truths.
  - chongli 13y ago
    DrRacket is a very big language. How does it compare with using a much smaller language such as the Scheme used in SICP?
    - samth 13y ago
      DrRacket is an IDE that supports many languages. The curricula that Shriram has used at Brown, and that others have used in many other places uses a sequence of smaller languages designed for teaching.
    - skrishnamurthi 13y ago
      Our studies were on students using Beginning Student Language, the smallest of the languages built into DrRacket. It is much smaller than the Scheme used in SICP.