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Pyret – A language exploring scripting and functional programming

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Re: Pyret – A language exploring scripting and functional programming

#11

Post by Insanity »

The annoying banner was distracting from the actual content unfortunatenly. From what I did see I don't see a reason to start using it in education to be honest. I don't see the problem with just teaching Java or Python. Sure it might be a bit harder, but it's what you'll end up using in the real world

Re: Pyret – A language exploring scripting and functional programming

#12

Post by xearl »

sdegutis wrote: post #3

> "while exploring the confluence of scripting and functional programming" Scripting and functional go amazing together, as long as it's (mostly) dynamic typing. In general, types really just get in the way when scripting or prototyping or trying to do anything fast, especially when you don't know the types of data you're going to be working with ahead of time, e.g. when it comes from a file or from an external API,…

> "In general, types really just get in the way when scripting or prototyping or trying to do anything fast"

I've found the opposite of that claim to be true. Types are absurdly helpful in prototyping or trying to do anything fast, especially when exploring data coming from a file or an external API.

Anecdotes aside, BinTree in the example is both a data type and a type testing function ("detector") of signature `Any -> Bool`. See http://www.pyret.org/docs/latest/Declarations.html#%28part._... for details.

Re: Pyret – A language exploring scripting and functional programming

#13

Post by makmanalp »

mattangriffel wrote: post #4

As someone who teaches coding to beginners for a living (I founded One Month and I teach Python to business students at Columbia University), this language looks really intimidating to beginners. Maybe Pyret isn't for beginners, and it's intended to teach people who already have some basic knowledge more advanced concepts like functional programming. That's fine. But to a total beginner, the syntax of Pyret is defini…

Annotations are optional. This is equally valid:

  fun square(n):
    n * n
  end
Not that different after all! And I say this as a lover of python and significant whitespace, but not having it at first would be easier.

Re: Pyret – A language exploring scripting and functional programming

#14

Post by danso »

Example from the OP:

        fun to-celsius(f):
          (f - 32) * (5 / 9)
        end
What's the justification for allowing the use of hyphens/dashes in reference names, when underscores would seemingly provide the same purpose? One of the most common problems I notice in newbie code is inconsistency in using whitespace, e.g. `a-b` vs `a - b`, though in that situation, for Python and virtually every other language I've used, those both result in subtracting b from a. But in Pyret, it seems that `a-b` would be interpreted as a reference? That seems needlessly confusing for no benefit in readability over using snakecase.

Beginners frequently have issues with grammar, that is, they are pretty much unaware of it when trying to figure out the many other things they have to learn about programming. Even in SQL, I forget that it must be quite confusing for beginners to parse out the meaning of the `` in something as simple as:

     SELECT mytable.*, (a * b) AS myproduct, 
          COUNT(*) AS the count
     FROM mytable ...
Doesn't seem worth it to make the hyphen, which is so frequently associated with subtraction and negative numbers, have just a decorative meaning when used between word tokens (as opposed to subtraction of values represented by variables).

Re: Pyret – A language exploring scripting and functional programming

#15

Post by justinpombrio »

mattangriffel wrote: post #4

As someone who teaches coding to beginners for a living (I founded One Month and I teach Python to business students at Columbia University), this language looks really intimidating to beginners. Maybe Pyret isn't for beginners, and it's intended to teach people who already have some basic knowledge more advanced concepts like functional programming. That's fine. But to a total beginner, the syntax of Pyret is defini…

The type annotations are optional, so you can write:

    fun square(n):
      n * n
    end
In fact, I believe the major motivation for making the type system optional was to not force beginning students to write types.

Re: Pyret – A language exploring scripting and functional programming

#16

Post by Jtsummers »

sdegutis wrote: post #3

> "while exploring the confluence of scripting and functional programming" Scripting and functional go amazing together, as long as it's (mostly) dynamic typing. In general, types really just get in the way when scripting or prototyping or trying to do anything fast, especially when you don't know the types of data you're going to be working with ahead of time, e.g. when it comes from a file or from an external API,…

My intuition from other languages is that it's a type and a set of constructors. leaf constructs an instance of type BinTree, as does node(4, leaf, leaf). This also matches how it's used in the where clause.

The documentation seems to verify my intuition: http://www.pyret.org/docs/latest/A_Tour_of_Pyret.html#%28par...

Re: Pyret – A language exploring scripting and functional programming

#17

Post by eykanal »

jstimpfle wrote: post #9
eykanal wrote: post #2

So, as someone without too much experience in language development, the concept of having unit tests being an extension of the functions themselves seems very interesting. Clearly this doesn't work for all scenarios—multiple functions interacting, any sort of GUI interaction—but that's a very intriguing concept.

Is there something that prevents you from making functions that only check how other functions interact?

No, not at all. The point is that there's specific syntax in the language for making this part of the function definition, as it were. New concept for me.

Re: Pyret – A language exploring scripting and functional programming

#19

Post by juliendorra »

danso wrote: post #14

Example from the OP: fun to-celsius(f): (f - 32) * (5 / 9) end What's the justification for allowing the use of hyphens/dashes in reference names, when underscores would seemingly provide the same purpose? One of the most common problems I notice in newbie code is inconsistency in using whitespace, e.g. `a-b` vs `a - b`, though in that situation, for Python and virtually every other language I've used, those both res…

On the other end, I love that Calca (mac and iPhone app and language) allows to use spaces in function or variable names. It's so natural.

Re: Pyret – A language exploring scripting and functional programming

#20

Post by jswrenn »

danso wrote: post #14

Example from the OP: fun to-celsius(f): (f - 32) * (5 / 9) end What's the justification for allowing the use of hyphens/dashes in reference names, when underscores would seemingly provide the same purpose? One of the most common problems I notice in newbie code is inconsistency in using whitespace, e.g. `a-b` vs `a - b`, though in that situation, for Python and virtually every other language I've used, those both res…

Pyret inherits hyphens-in-identifiers from Scheme/Racket. One of Pyret's largest users, Bootstrap [1], has long-used a dialect of Scheme, and has recently introduced a curriculum that uses Pyret. For these users, "virtually every other language" allows for hyphens in identifiers.

Scheme mitigates the spacing issue with s-expressions. Pyret attempts to mitigate it by enforcing that operators should be separated from their operand with at least one space.

(Disclosure: I am an occasional developer of Pyret.)

[1] http://www.bootstrapworld.org/

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