def is_subseq(x, y):
it = iter(y)
return all(any(c == ch for c in it) for ch in x)
assert is_subseq('india', 'indonesia')
assert is_subseq('oman', 'romania')
assert is_subseq('mali', 'malawi')
assert not is_subseq('mali', 'banana')
assert not is_subseq('ais', 'indonesia')
assert not is_subseq('ca', 'abc')
Also works for any iterables:
assert is_subseq(['i', 'n', 'd', 'i', 'a'],
['i', 'n', 'd', 'o', 'n', 'e', 's', 'i', 'a'])
UPDATE
Stefan Pochmann suggested this.
def is_subseq(x, y):
it = iter(y)
return all(c in it for c in x)
Both versions uses iterators; Iterator yields items that was not yielded in previous iteration.
For example:
>>> it = iter([1,2,3,4])
>>> for x in it:
... print(x)
... break
...
1
>>> for x in it: # `1` is yielded in previous iteration. It's not yielded here.
... print(x)
...
2
3
4