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Comment by wearywanderer | Hacker News Reader

I know different pedagogical approaches work for different people, but in my experience the fastest and easiest way to learn Lisp is to bite the bullet and jump right into it. I think when it comes to the parentheses of Lisp, the premise is straightforward; there just isn't a whole lot to actually learn. I believe most of the difficulty comes from people psyching themselves out before they even try. That describes my personal experience with the matter anyway.

Also with regards to prefix notation being unintuitive: We already teach something very similar to schoolchildren learning arithmetic:

      1
    + 2
    ---

Here, as with (+ 1 2), the operator is on the left most side. The operands are arranged horizontally in lisp instead of vertically, but the supposed weirdness of the operator being on the left doesn't seem to bother people when it comes to arithmetic.

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Invoking something at the command line is also prefix notation, and it's something programmers do all the time.

I always read that as (1 + 2). I read it left to right, then top to bottom, so it would read as [null, "1", "+", "2"] and not as [null, "+", "1", "2"].

Tbh I generally vocalize (+ 1 2) as "one plus two". Casual English usually uses infix notation, but I think "add one and two" is valid and generally understood.

What about (sqrt (+ (+ 3 3) (+ 4 4))) read as "square root of the sum of the product of 3 by 3 and 4 by 4" instead of √(3^2+4^2) where √ is prefix, + is infix, ^ is exponent, not to speak of implicits precedences.

in lambdatalk (http://lambdaway.free.fr) one could go beyond and mix html/css using the same syntax, for instance

{div {@ style="color:red"} the hypotenuse of a square triangle (3,4) is equal to {sqrt {+ {* 3 3} {* 4 4}}} }

which can be read like this « write in a div html element, whose style attribute is color red, the hypotenuse of a square triangle (3,4) is equal to the square root of the sum of the product of 3 by 3 and 4 by 4 »

is displayed as « the hypotenuse of a square triangle (3,4) is equal to 5 »

In fact prefixed parenthesis expressions follow the way we think and speak.

Apl can be read as english as well, and frequently also obviates nesting (lisp revels in it, but humans don't deal well with deeply nested structures). Your example: 0.5*⍨+/×⍨3 4. That is, the 0.5 power of the sum of the squares of the legs. But notice: uniform precedence (like lisp) and no nesting whatsoever.

(√ as sqrt is not generally primitive, though it can be trivially implemented.)

Why is this comment greyed?

I almost wonder if Lisp pedagogy would be improved if the ‘+’, ‘-‘, etc. operators weren’t introduced for some time, and maybe instead ‘add’ or ‘subtract’ were taught instead. There’d be less knee-jerk opposition to the lack of infix notation.

Then it would become complaint against verbosity by those who only saw first lesson of a lisp book.

For someone who started learning Lisp way way late in my programming journey, I would not have appreciated it had I not went through half dozen other languages before. The sheer simplicity of the foundational concept is liberating.

That simplicity means Lisp actively encojrages exploration (which is why you see so many Lisp dialects). Unfortunately, most people don't really learn anything new unless they were forced into it. Most people, aren't into exploration. They treat language as a short-term tool to get paycheck, and anything making them use more braincells, even to their own long-term benefit, is an annoyance.

To each their own, its just that as good as Lisp is, its MO don't map well with that of most populace.

> complaint against verbosity

Not an unjustified one, in fairness. Lisp tends to prefer long, descriptive names.

Agreed. Even more of a reason to not make + into add and - into subtr.

I've thought about how the verbosity can be avoided, but at certain level of complexity, it is better to have long descriptive names, but I'm not experienced enough with big projects to propose a solution.

it also has macro forms which expand into zillions of 'lines of code' during compilation

I've always read

      1
    + 2
    ---

as [1 2 +]. I guess it's a difference in perception.

> The operands are arranged horizontally in lisp instead of vertically, but the supposed weirdness of the operator being on the left doesn't seem to bother people when it comes to arithmetic.

I'm not sure I agree. I would argue that people read your example left to right, top to bottom, which would be "1 + 2". At least for people that read their native language this way. Maybe people who read from right to left would read "1 2 +" and be predisposed to Forth?

I seem to recall mixed columnar addition and subtraction:

which was read as "3 + 4 - 5 = 2"

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