With Category Theory, Mathematics Escapes from Equality (2019)

Re:With Category Theory, Mathematics Escapes from Equality (... by a1369209993 on Sunday March 27, 2022 @01:31AM (#30817942)

> Leibniz's rule

  > x=y  =>  f(x)=f(y)

Eh, it's useful in some cases, especially from a theoretical perspective, but...

  x = 0.0
  y = -0.0
  f = \x(copysign(1,x))
  
  x = "foo"
  y = "f"+"o"+"o"
  f = debug.dump-pointer

...pragmatically I'm not interested in a programming language where it does hold. It prohibits too many important utility functions.

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Re:With Category Theory, Mathematics Escapes from Equality (... by User23 on Sunday March 27, 2022 @11:55AM (#30821232)

You’re not even wrong. I suggest that you at least take the five minutes to read the wikipedia summary on predicate transformers before posting a replying in which you observably have no idea what you’re talking about.

Briefly, predicate transformers are functions about the behavior of a language, not functions in the language. In that model predicates are pure functions over the program state space and predicate transformers are functions from predicates to predicates. Clearly your objections are inapplicable.

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