View source code
Display the source code in std/algorithm/comparison.d from which this page was generated on github.
Report a bug
If you spot a problem with this page, click here to create a Bugzilla issue.
Improve this page
Quickly fork, edit online, and submit a pull request for this page. Requires a signed-in GitHub account. This works well for small changes. If you'd like to make larger changes you may want to consider using local clone.

Function std.algorithm.comparison.among

Find value among values, returning the 1-based index of the first matching value in values, or 0 if value is not among values. The predicate pred is used to compare values, and uses equality by default.

uint among(alias pred, Value, Values...) (
  Value value,
  Values values
)
if (Values.length != 0);
template among(values...) ;

Function among

Template among

Contained Functions

NameDescription
among

Parameters

NameDescription
pred The predicate used to compare the values.
value The value to search for.
values The values to compare the value to.

Returns

0 if value was not found among the values, otherwise the index of the found value plus one is returned.

See Also

find and canFind for finding a value in a range.

Example

assert(3.among(1, 42, 24, 3, 2));

if (auto pos = "bar".among("foo", "bar", "baz"))
    writeln(pos); // 2
else
    assert(false);

// 42 is larger than 24
writeln(42.among!((lhs, rhs) => lhs > rhs)(43, 24, 100)); // 2

Example

Alternatively, values can be passed at compile-time, allowing for a more efficient search, but one that only supports matching on equality:

assert(3.among!(2, 3, 4));
writeln("bar".among!("foo", "bar", "baz")); // 2

Authors

Andrei Alexandrescu

License

Boost License 1.0.