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Can we talk about the library in Boise where I saw a kid debug his first while loop with a pencil?
He traced every line on paper for 20 minutes because he refused to touch the keyboard until he knew what each pass would print, and that pencil habit is the whole reason his loop finally made sense.
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the_sean23h ago
The "refused to touch the keyboard until he knew what each pass would print" part is what gets me, because I kinda see it the other way. Tracing all 20 minutes by hand means he sat there guessing at what the code would do instead of just running it and watching. Half the value of a while loop is seeing it actually loop, and a pencil can't show you an off-by-one blowing up at runtime or a variable that never changes. Paper teaches you to plan, sure, but the computer teaches you what really happens when your plan is wrong. Kid got there in the end, but I bet he'd have gotten there faster by typing it and breaking it on purpose.
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laura48623h ago
Getting where he got by hand is a real skill though. I did the same thing in my first Java class and my loop ran off the end of the array because I never checked what happened after the last index, and man that error message taught me more than any lecture. You end up picturing the machine in your head, which sticks with you way longer than just watching a printout scroll by. Both ways work, but the slow one builds something the fast one skips.
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