searchSubsequence

Find first index of a subsequence.

Similar: hasPrefix, hasInfix, hasSuffix, hasSubsequence.
Similar: search, [scan], find.

function searchSubsequence(x, y, fc, fm)
// x:  an iterable
// y:  search subsequence
// fc: compare function (a, b)
// fm: map function (v, i, x)

const xiterable = require('extra-iterable');

var x = [1, 2, 3, 4];
xiterable.searchSubsequence(x, [2, 4]);
// → 1

xiterable.searchSubsequence(x, [-2, -4]);
// → -1

xiterable.searchSubsequence(x, [-2, -4], (a, b) => Math.abs(a) - Math.abs(b));
// → 1

xiterable.searchSubsequence(x, [-2, -4], null, v => Math.abs(v));
// → 1

References

• Data.List.isSubsequenceOf: Haskell
• List-Extra.isSubsequenceOf: elm