I ve used List.exists( ), i woudl like to know if there is an equivalent for Db.
If i have a function f(e) : bool, i would like to know if there is at least one element e, with f(e) -> true. Currently i use the Db.intmap_fold_range( ), but it iterates over all the Db, whereas it would be better for performances to stop at the first return true.
I suppose your DB is an IntMap if you can use Db.intmap_fold_range.
This is a sample code :
// Testing function
f(key, val) = key == 42
// Check existence in "mymap"
res = IntMap.exists(f, /mymap)
If you look at the source code, you can see that it is implemented for folding only on the necessary elements :) (File: stdlib/core/map/map.opa)
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I ve used List.exists( ), i woudl like to know if there is an equivalent for Db. If i have a function f(e) : bool, i would like to know if there is at least one element e, with f(e) -> true. ...
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