Expression matching Ocaml -

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my question simple: how translate c code :

if (x == y + 1)   // code else if (x == y - 1)   // code else if (x == y + 2)    ....

basically thinking of using pattern matching seemed appropriate. unfortunatly pattern doesn't work:

match x | y + 1 -> code | y - 1 -> code | y + 2 -> code | _ -> code

the compiler doesn't seem happy , have found out, expressions on pattenr matching did not tolerated. therefore tried putting them in values thusly:

let v1 = y + 1 in let v2 = y - 1 in let v3 = y + 2 in match x | v1 -> code | v2 -> code | v3 -> code | _ -> code

unfortunatly warnings saying values v1 v2 , v3 unused , the match cases use them unused too.

how can match expression other expressions?

thanks

actually, c code valid ocaml code.

if x = y + 1   (* code *) else if x = y - 1   (* code *) else if x = y + 2    ....

pattern matching not replacement if then, has completly different purpose. ocaml allows construct types such type 'a option = none | of 'a , pattern matching should used deconstruct types. sould not used other purposes.


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