what is the meaning of "let x = x in x" and "data Float#" in GHC.Prim in Haskell -

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i looked @ module of ghc.prim , found seems datas in ghc.prim defined data float# without =a|b, , functions in ghc.prim defined gtfloat# = let x = x in x.

my question whether these definations make sense , mean.

i checked header of ghc.prim below

{- generated file (generated genprimopcode). not code used. purpose consumed haddock. -}

i guess may have relations questions , please explain me.

it's magic :)

these "primitive operators , operations". hardwired compiler, hence there no data constructors primitives , functions bottom since not expressable in pure haskell.

(bottom represents "hole" in haskell program, infinite loop or undefined examples of bottom)

to put way

these data declarations/functions provide access raw compiler internals. ghc.prim exists export these primitives, doesn't implement them or (eg code isn't useful). of done in compiler.

it's meant code needs extremely optimized. if think might need it, useful reading primitives in ghc


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