Contains¶

Observable.contains(value, comparer=None)¶

Determines whether an observable sequence contains a specified element with an optional equality comparer.

Example 1 - res = source.contains(42) 2 - res = source.contains({ “value”: 42 }, lambda x, y: x[“value”] == y[“value”)

Keyword parameters: value – The value to locate in the source sequence. comparer – {Function} [Optional] An equality comparer to compare elements.

Returns an observable {Observable} sequence containing a single element determining whether the source sequence contains an element that has the specified value.

Observable.find(predicate)¶

Searches for an element that matches the conditions defined by the specified predicate, and returns the first occurrence within the entire Observable sequence.

Keyword arguments: predicate – {Function} The predicate that defines the conditions of the

element to search for.

Returns an Observable {Observable} sequence with the first element that matches the conditions defined by the specified predicate, if found otherwise, None.

Observable.find_index(predicate)¶

Searches for an element that matches the conditions defined by the specified predicate, and returns an Observable sequence with the zero-based index of the first occurrence within the entire Observable sequence.

Keyword Arguments: predicate – {Function} The predicate that defines the conditions of the

element to search for.

Returns an observable {Observable} sequence with the zero-based index of the first occurrence of an element that matches the conditions defined by match, if found; otherwise, -1.

Observable.is_empty()¶

Determines whether an observable sequence is empty.

Returns an observable {Observable} sequence containing a single element determining whether the source sequence is empty.

Observable.some(predicate=None)¶

Determines whether some element of an observable sequence satisfies a condition if present, else if some items are in the sequence.

Example: result = source.some() result = source.some(lambda x: x > 3)

Keyword arguments: predicate – A function to test each element for a condition.

Returns {Observable} an observable sequence containing a single element determining whether some elements in the source sequence pass the test in the specified predicate if given, else if some items are in the sequence.