We've used the
map() operator in some of the previous examples. The higher order functions which transform the incoming values into something else are called transformations. The higher order functions that can be invoked on an
Observable instance, producing a new
Observable instance from it, are called operators. The transforming operators transform the elements emitted from the source
Observable instance in some way.
The rectangle in the center of the diagram represents the operator (function). It transforms its input (circles) into something else (triangles). The arrow above the rectangle represents the source
Observable instance, the colored circles on it represent
notifications emitted in time, and the vertical line at the end is the
notification. The arrow below the rectangle is the...