Somewhere closer to the end of the talk, Mr. Meijer says that segregation of common parts

of a function from the distinct parts is only possible with lazy evaluation (with the two clouds

drawn on the board). Didn't he really mean functional composition instead, which is more

general than lazy evaluation? If the distinct parts have no side-effects and the common part has

no influence on the distinct parts besides parametrization (as is the case with pure functions),

then you can also call the common part as a function with distinct parts as pure functional or

value parameters to that common function.

 

Of course you might save some computations with lazy evaluation, but I am quite sure I have

applied this technique with eager evaluation as well!

 

Am I missing something?