Built-in macros

Needless to say the Julia team has put macros to good use. To get the help information about a macro, enter a ? in the REPL, and type @macroname after the help> prompt, or type help("@macroname"). Apart from the built-in macros we encountered in the examples in the previous chapters, here are some other very useful ones (refer to the code in Chapter 7\built_in_macros.jl).

Testing

The @assert macro actually exists in the standard library. The standard version also allows you to give your own error message, which is printed after ERROR: assertion failed.

The Base.Test library contains some useful macros to compare the numbers:

using Base.Test
@test 1 == 3

This returns ERROR: test failed: 1 == 3.

@test_approx_eq tests whether the two numbers ...

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