Document subscribe as a teminal operator (#5419)

Signed-off-by: Ben Sherman <[email protected]> Signed-off-by: Paolo Di Tommaso <[email protected]> Co-authored-by: Paolo Di Tommaso <[email protected]> Co-authored-by: Christopher Hakkaart <[email protected]>
nextflow-io · Oct 22, 2024 · 24d595c · 24d595c
1 parent d6c684b
commit 24d595c
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/docs/reference/operator.md b/docs/reference/operator.md
@@ -1393,7 +1393,7 @@ See also: [countLines](#countlines)
 
 ## subscribe
 
-*Returns: the source channel*
+*Returns: nothing*
 
 The `subscribe` operator invokes a custom function for each item from a source channel:
 
@@ -1425,6 +1425,10 @@ The `subscribe` operator supports multiple types of event handlers:
 :language: console
 ```
 
+:::{note}
+Unlike most operators, `subscribe` is a *terminal operator* and does not emit any values. It should only be used for *side effects*, such as printing to the console, writing to a file, or making HTTP requests.
+:::
+
 Available options:
 
 `onNext`