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JavaScript Handling Errors

Stheven Cabral
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Stheven Cabral
Full Stack JavaScript Techdegree Graduate 29,854 Points
Posted by Stheven Cabral
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Stheven Cabral
Full Stack JavaScript Techdegree Graduate 29,854 Points

Why doesn't checkStatus have parenthesis when invoked?

Why doesn't Guil include () when passing checkStatus inside .then()? When do you and when do you not use () in front of a function name when calling that function?

1 Answer

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

You always use parentheses when calling a function, but in the example you mention it is not being called but is being passed as an argument (commonly known as a "callback").

The actual invocation will occur at a later time (controlled by the "then").