filter
accepts
1 input stream,
a predicate function
-
❯When the input stream emits a value, it is given to the
predicate:- If the predicate returns
✔ true, the value is emitted - Otherwise, the value is ignored
- If the predicate returns
returns a new stream of filtered values
map
accepts
1 input stream,
a project function
-
❯When the input stream emits a value, it is given to the
projectfunction and the resulting value is emitted
returns a new stream of projected values
Revised on Monday, 8 Oct. 2018
Project vs Predicate
In the video example, ▬ isEven accepts a number as an argument:
- If it is an even number, it returns
✔ true - Otherwise, it returns
✘ false
It is used as:
- a project function on
❚ map - a predicate function on
❚ filter
A predicate returns ✔ true or ✘ false.
Learn more about project and predicate.
See also
Freelance Developer Advocate. Motion graphics with code. JavaScript and Elm. cedricsoulas.com
Join the Newsletter
Receive my latest news, product updates and programming visualizations. You can unsubscribe at any time.