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iOS Objective-C Basics (Retired) Foundation Framework NSNumber

cannot pass the exam when use different assignment method

When using: NSNumber *planck= [NSNumber numberWithFloat:6.626]; cannot pass it. While using: NSNumber *planck=@6.626; it works. Why?

1 Answer

Roberto Alicata
PLUS
Roberto Alicata
Courses Plus Student 39,959 Points

With the @ symbol you use the Objective-C Literals.

"In Objective-C, any character, numeric or boolean literal prefixed with the '@' character will evaluate to a pointer to an NSNumber object initialized with that value. Cā€™s type suffixes may be used to control the size of numeric literals." from clang