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0 points_0w8t8y ago0 comments

Git rebase alters the structures that are relevant for me, like heads of named branches. In Haskell let bindings are immutable. To reference to the results one has to put them into new bindings. I.e. if Git was purely functional, the rebase would create new names for branches.

0 comments

tathougies8y ago

You can easily shadow a name in a let binding in Haskell

For example,

let x = 5 in let x = 6 in putStrLn (show x)

would print 6. Unless you turn on compiler warnings, there is never a need to choose new names for variables if the old version is no longer needed.

catnaroek8y ago

Shadowing isn't the same thing as redefining. Try evaluating the following expression:

    let x = 4 ; f y = x + y in let x = 6 in f 10

rootlocus8y ago

If you want immutable branches, you can use tags https://git-scm.com/book/en/v2/Git-Basics-Tagging

masklinn8y ago

> In Haskell let bindings are immutable.

Haskell has mutable refs. That's what Git branches are.

catnaroek8y ago

But the contents of a mutable ref aren't let-bound.

fiatjaf8y ago

So your entire point amounts to naming?

j / k navigate · click thread line to collapse

0 comments

tathougies8y ago

You can easily shadow a name in a let binding in Haskell

For example,

let x = 5 in let x = 6 in putStrLn (show x)

would print 6. Unless you turn on compiler warnings, there is never a need to choose new names for variables if the old version is no longer needed.

catnaroek8y ago

Shadowing isn't the same thing as redefining. Try evaluating the following expression:

    let x = 4 ; f y = x + y in let x = 6 in f 10

rootlocus8y ago

If you want immutable branches, you can use tags https://git-scm.com/book/en/v2/Git-Basics-Tagging

masklinn8y ago

> In Haskell let bindings are immutable.

Haskell has mutable refs. That's what Git branches are.

catnaroek8y ago

But the contents of a mutable ref aren't let-bound.

fiatjaf8y ago

So your entire point amounts to naming?

j / k navigate · click thread line to collapse