erg/doc/EN/syntax/31_pipeline.md

Pipeline Operator

The pipeline operator is used like this:

assert f(g(x)) == (x |> g |> f)
assert f(g(x, y)) == ((x, y) |> g |> f)

In other words, the order Callable(object) can be changed to object |> Callable. Pipeline operators can also be used on methods. For methods, object.method(args) changes to object |>.method(args). It looks like just an increase in |>, but since the bond strength is low, the amount of () may be reduced.

rand = -1.0..1.0 |>.sample!()
log rand # 0.2597...
1+1*2 |>.times do log("a", end: "") # aaa
# without `|>`, the following will be `evens = (1..100).iter().filter(i -> i % 2 == 0).collect(Array)`
evens = 1..100 |>.iter |>.filter i -> i % 2 == 0 |>.collect Array
# or
_evens = 1..100\
    .iter() \
    .filter i -> i % 2 == 0 \
    .collect Array

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