Re: What is process_lines? and general complaint on the new manual
- Posted by ne1uno Jan 20, 2011
- 1897 views
It used to be that all functions required a return value, or else an error would be thrown. Now, when you call a function, you don't need a return value ... Kind of makes the procedure redundant ...
I see. May I ask the reasoning behind this change? Knowing nothing about language design, it's not obvious to me.
often you will see the function return assigned to a VOID or JUNK object and then never used. sometimes it is simpler to just ignore the return of an error value.
the error return of process_list() is what the caller of the function decides it is. this would probably be used in a real program, but you can also observe the output of those 20 lines to decide if there were an error. but is just an example.
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I am under the impression that process_lines() is like read_lines(), but with user-defined mojo. Like custom_sort() vs sort(). Do I assume correctly?
process_lines() and read_lines() work quite differently though and that's throwing me off. read_lines() returns a result sequence but process_lines() does not, I think.
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I want to extract and build a sequence of names that only begin with 'A'. Very simple. Would process_lines() be good here, and how do we do it?
filter() or build_list() could return such a modified sequence.
