(jeffa) 3Re: Expand Ranges in Lists of Numbers

"Sometimes I wish one line blocks for if-else statements didn't require brackets..."

I use to say the same thing until i realized they don't:

print "that's the answer" if $answer == 42;

die "that's not your file!" unless -o $file;
[download]

A caveat i teach my C++ lab students (i am a graduate teaching assistant at MTSU) is that even though braces are optional for one line blocks, they should get in the habit of using them always. Why? Because 9 times outta 10 you will want to add a second line in the near future. Murphy's law or something ... ;)

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

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Re: (jeffa) 3Re: Expand Ranges in Lists of Numbers by The Mad Hatter (Priest) on Jun 09, 2003 at 02:37 UTC
`print "that's the answer" if $answer == 42;` [download] Yeah, but there is no "elegant" way to do this `if ($answer == 42) print "that's the answer"; else print "you're a jerk. a complete kneebiter.";` [download] You'd have to do something like `print "that's the answer" if $answer == 42; print "you're a jerk. a complete kneebiter." unless $answer == 42;` [download] 9 times outta 10 you will want to add a second line in the near future. Heh. I bet at first they ignore your advice. Then they keep on having to add braces and they realize that you're right. ; )	[reply] [d/l] [select]
(jeffa) 5Re: Expand Ranges in Lists of Numbers by jeffa (Bishop) on Jun 09, 2003 at 04:00 UTC
And that is where you use the ternary op: `print( $answer == 42 ? "that's the answer" : "that is the answer" );` [download] The students who have to take Comp Sci One (i ~~teach~~ administer the lab portion, BTW) are usually either Computer Science, Math, Engineering, or Industrial Studies majors. Rarely do the Math majors enjoy C++ ... we GTA's just do whatever we can do get them through the class. Watching them puzzle over differentiating between assignment and equality can be amusing, especially the first time they encounter `i = i + 1`. The Engineering and IS majors tend to appreciate the course a bit more than the Math majors ... anyone with a different major probably took the course by mistake or because they didn't know any better - but there are a few "rogues" who know what they are doing. Those students and the CS majors are the ones that i focus mainly on - anyone who will be taking more CS courses. Everyone else is just taking the course to fullfill prerequisits, and won't be pursuing programming probably ever again. In other words, about 90% of the class ignores my advice. ;) jeffa L-LL-L--L-LL-L--L-LL-L-- -R--R-RR-R--R-RR-R--R-RR B--B--B--B--B--B--B--B-- H---H---H---H---H---H--- (the triplet paradiddle with high-hat)	[reply] [d/l] [select]
Re: (jeffa) 5Re: Expand Ranges in Lists of Numbers by The Mad Hatter (Priest) on Jun 09, 2003 at 12:16 UTC
And that is where you use the ternary op Yeah, I know, but it still isn't quite the same. (Don't mind me, I like to nitpick little stuff; I'm odd like that. :) In other words, about 90% of the class ignores my advice. ;) Heh. I imagine it can be fun at times. ; )	[reply]