scheme - Why are `not-equal?` and similar negated comparisons not built into Racket? -

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in racket (and other schemes, can tell), way know of check whether 2 things not equal explicitly apply not test:

(not (= num1 num2))  (not (equal? string1 string2))

it's (not (that-big-of-deal?)), it's such common construction feel must overlooking reason why it's not built in.

one possible reason, suppose, can rid of not using unless instead of when, or switching order of true/false branches in if statement. doesn't mimic reasoning you're trying convey.

also, know negated functions easy define, <=, example, , built in.

what design decisions not having things not-equal?, not-eqv?, not-eq? , != in standard library?

first, correct (not (that-big-of-a-deal?))1

the reason racket doesn't include out of box because adds lot of primitives without benefit. admit lot of languages have != not equal, in java, if want deep equality check using equals() (analogous equal? in racket), have manually invert result ! yourself.

having both <= , > (as >= , <) convenient enough cause original designers of language include it.

so no, there isn't deep reason why there not shortcut having not-eq? function built racket. adds more primitives , doesn't happen add benefit. still need not exist on own anyway.

1i love pun way. have imaginary internet points.


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