What's the advantage of using function table

[Mike]

In C, we can typedef pointer to functions, and therefore use function
tables. But what's the advantage of using function table?

Thanks,

Mike

[Thomas Matthews]

Mike wrote:

In C, we can typedef pointer to functions, and therefore use function
tables. But what's the advantage of using function table?

Thanks,

Mike

Example 1: Switch{ing} based on strings.

The C language does not allow a string variable type
inside a switch statement. One solution to this
dilemma is to use a table of <string, function_ptr>
records. Search for the string, and if found,
execute the function via the function pointer in
the record.

This is very handy in Menu processing for User
interfaces.
Example 2: Event delegation.
In many operating systems, they have a table
of functions to execute for a given event.
The table may have records such as
<event_ID, pointer to event function>
Again, match the event ID and execute the
function via the pointer.

Example 3: Factory pattern.

Example 4: Scripting.
One could have an engine that iteraters
through a table or list of function pointers,
executing each one. Each table or list can
be consider as a script or batch of instructions.

--
Thomas Matthews

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