 Question for #scheme ☯️ kings & queens 👑 ! Are there an alternative to clojure's alter-var-root https://clojuredocs.org/clojure.core/with-redefs in scheme? Imagine I have a module `(X)` with `(define a 1) (define-public (f x) (+ x a))` and module `(Y)` that has `#:use-module (X)`. In `(Y)` want to alter a from `(X)` in a way that would also affect `f`. Example: (being in module `(Y)`): `(alter! a 2) (equal? (f 3) 5) => #t` 14 comments
I'm not sure about this formulation. I want to update `x` from `(X)` "globally": in a way that everything from `(X)` that'd have `x` referenced would also update it to the new value. Imagine that you have a module already written by someone that does the job you want to, but there is only one variable (example `(define pi 3.14)` ) that you want just override but otherwise would like everything to work as previously. Wouldn't like to copy-paste a one of code it won't update setted variable's value in all procedures of `(X)` that uses `x`. `(define (square r pi) (* r r pi))` <-- here pi will stay 3.14 when `square` will be called from `(Y)`  @shegeley @wingo @cwebber @monkey1 so you just need to create an alias? In that case (define my-alias the-original) works fine except when dealing with syntax. In that case, you can do (define-syntax my-alias Might have left something out of that bcs im writing from my phone, currently on the move, so lmk if that didn't work and ill take a look.  |
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@shegeley @rml @cwebber most schemers are republicans, in the anti-monarchist sense :) but if the intended use case is global monkeypatching, then in guile `set!` is your tool. if `a` is exported, then just `set!` on `a`. if not, `(set! (@@ (X) a) new-val)`