Notation for mappings uses the ...?

Notation for mappings uses the ...?



f : ℝ ↦ ℤ

which you can read as "There is a function called f that takes a real number as input and maps it to an integer."
Here, the set that comes before the arrow is called the domain of the function, and the set after the arrow is called the target.

In programming, you can read it as "There is a function called f which has one real argument and returns an integer."

In other words, the set notation above is equivalent to the common programming notation:

integer f (real) ← equivalent → f : ℝ ↦ ℤ

So the colon-arrow notation can be thought of as a programming syntax.

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