concatAll

signature: concatAll(): Observable

In many cases you can use concatMap as
a single operator instead!

Example 1: concatAll with observable

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jsBin |
)

Example 2: concatAll with promise

Example 3: Delay while inner observables complete

( StackBlitz |
|
jsFiddle )

• concatAll
  - Official docs
• 
  - André Staltz