In the first description of the language LISP, from March 1959 (AIM-008), John McCarthy had used the names "first" and "rest", instead of what later will be called "CAR" and "CDR".
The names of "CAR" and "CDR" appear to have come from the students who worked at the practical implementation of the LISP interpreter on an IBM 704, and unfortunately we have remained stuck with them, like also with other features that were intended only for a temporary use, until being replaced in the "final version" (which was abandoned).
Just FYI, many of these are also done in Scheme and its derivative Racket. They kept lambda (but even Python did that), but progn -> begin, setq -> set!, car -> first, and so on.
> Also my main objection to Lisps is still the horrible bracket syntax. Yes it's unambiguous and easy to parse, but it's HORRIBLE to read and edit.
I have pretty mixed feelings at this point. I don’t mind it for normal programming, but when I do numerical programming (physics models, etc.) you often get extremely long and verbose expressions that are IMO difficult to parse compared to the math-like infix operator notation used in other languages.
I wonder if we were raised on tree based algebra if math would be easier to do, or harder.
Like, solve for x.
(= (+ (* 2 x) 3) 11)
(= (* 2 x) (- 11 3))
(= (* 2 x) 8)
(= x (/ 8 2))
(= x 4)
(= (+ (pow x 2)
(pow y 2))
(pow r 2))Perhaps this exists already somewhere?
The helloworld of macros lets you do `(infix 1 + 2)`:
(defmacro infix [a op b]
~(,op ,a ,b))
(defmacro infix [& toks]
(def prec {'+ 1 '- 1 '* 2 '/ 2 '% 2})
(var pos 0)
(defn climb [min-p]
(var left (toks pos))
(++ pos)
(while (>= (get prec (get toks pos) -1) min-p) # nil/operand -> -1, stops the loop
(def op (toks pos))
(++ pos)
(set left ~(,op ,left ,(climb (inc (prec op)))))) # inc => left-associative
left)
(climb 0))
Interesting question. Much of the difficulty does stem from mentally translating back and forth between conventional notation and s-exps too, since you can’t really avoid the standard notation when reading and writing math and physics papers. And current-day math and physics notation has been optimized to some extent for the infix notation; perhaps one would have invented more expressive higher-order functions or macros to denote s-exp math if that was what everyone used for centuries.
Statements are terminated by either a dedicated graphical character, in which case it's easy to forget the character and have a problem, or by a newline (or maybe a different white space character, but I haven't encountered that yet) in which case decent formatting of code may require a dedicated graphical character to indicate that the newline DOESN'T terminate the statement, in which case we have the same problem. Having newline-terminated statements without continuation character would be consistent, but would hamper readability because identifiers would need to be strictly limited in length to keep certain lines from exceeding available screen space (or alternatively readability would suffer from lines only being partially readable).
And that's before getting into the weeds of how mathematical notation is tricky (most people have learned infix notation at maths class in school, so they mightn't appreciate how horrible it is), how different types of brackets (round, square, curly) can have inconsistent semantics, the downsides to the various ways of indicating lexical blocks (brackets, white space, keywords,...), et cetera.
The ideal programming language would probably be one which allows switching between different syntaxes based on what works best for the user (for example, someone could write code in S-expressions, another person could have that code automatically translated into SRFI-119 Wisp expressions and work with it like that, a third person could then have it rendered into something more Lua-like,...). Which is something I think the Racket people are working on, but I may be mistaken.
Is static typing that important for a scripting language? From the intro to the book:
> And to be clear, I’m not going to try to convince you to bet your next startup on Janet, or even to use it in any sort of production setting. But I think it’s an excellent language for exploratory programming, scripting, and fun side projects.
It would be good to know order of magnitude anyway. Like, are we talking Ruby/Python level, etc.
I use Parinfer, which allows me to edit Janet as if it was an indentation-based language.
This normally matters very little, because a good editor will always insert a complete template whenever you type something like "if", "for", "while" etc.
Most programmers are blind to the syntax defects with which they are accustomed and they notice only the syntax defects with which they are unfamiliar.
I would prefer a language with a good syntax, but unfortunately which programming languages have survived in widespread use has a poor correlation with the technical qualities of a language and especially a really negligible correlation with how good its syntax was.
Roughly as fast as puc-rio Lua. It won't blow your socks off, but it's more than respectable.