Yellow Triangles !

[JackRabbit]

Greetings everyone.

This is more of a comment than a question but other comments are welcome.

On page 14, in the paragraph just before Figure 2.9, in the book it states:

Warnings are depicted by yellow triangles containing exclamation points—you can still run your program with them, but in general you should examine and correct them.

I am surprised that there are "grey area" errors in programming. Why are these yellow triangle errors allowed at run time? Any thoughts?

JR

[Fred]

JR,

The warnings are provided due to the fact the compiler can't know everything, so when there may be a problem, but it might not prevent program execution, the compiler presents the warning.  An example of a warning that does not impact program execution is declaring a variable that is not used in the program.  This does not cause any execution problems, but it does waste program resources and thus the warning.  There are others that will cause a run time error, such as calling a method from a class where the method is not defined.   This will become clearer as you progress through Steve's book and become more familiar with what produces a warning as opposed to what produces an error.

Fred

[JackRabbit]

Thank you again Fred.

For a newbie you sure know alot!

These forums + the book + the webinars = understanding Objective-C

One day I hope to help you.

JR