Re: pipes, scalar objects and on?

On Wed, Jul 19, 2023, at 12:08 PM, Olle Härstedt wrote: > 2023-07-18 18:50 GMT+02:00, Larry Garfield <larry@garfieldtech.com>: >> On Tue, Jul 18, 2023, at 4:47 PM, Olle Härstedt wrote: >> >>> Any comment on a pipe (or piped process) as a first-class value? When >>> you use |> the functions are immediately applied, which might not be >>> what you want. You can lazify it by wrapping it in a lambda, but I >>> think that decreases the value of the pipe concept in itself. One >>> strength is the ability to split the decision about what to glue >>> together from the decision on how to execute it. You kinda get some >>> light-weight metaprogramming ability that way. >>> >>> Well i guess such a pipe-concept is pretty far removed from the simple >>> pipe operator. :) And also already possible with existing OOP >>> concepts, callable classes, and now the (...) syntax. >> >> That's the function concat operator I have been mentioning. Concat can be >> implemented in terms of pipe, and pipe can be implemented in terms of >> concat, but I'd rather have both natively. >> >> For more on my thoughts there, see: >> https://peakd.com/hive-168588/@crell/aoc2021-review > > Right, I think I was thinking more of the pipeline design pattern than > the pipe operator. The concat operator will tell you THAT two > functions have been glued together, but you have no way to affect HOW > they are glued together. With the pipeline design pattern, you do: For > example, you could add a logger that logs each input and output in the > Pipe class without much hassle. > > The pipeline design pattern could still greatly benefit from some of > these RFCs tho, especially partial function application, I think. > > Olle OK, terminology mismatch. What you're calling "pipeline design pattern" I'm calling "that's literally what a monad is." :-) (More precisely, monads are the mathematical rules that a "fancy function concatenation" operation has to follow in order to still be composable cleanly. You could make pipeline-like things that don't follow those rules, but they'd be less useful.) Your logging example is literally the "writer monad," one of the standard monad examples. --Larry Garfield