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Rust
book

Rust

by Rheinwerk Publishing, Inc, Nouman Azam
April 2026
Intermediate
631 pages
16h 20m
English
Packt Publishing
Content preview from Rust

15.3    Repeating Patterns

Repetition in code often invites opportunities for refinement, and macros are powerful tools for such cases. By capturing and reusing patterns, macros simplify code structure, making it both more compact and easier to manage.

Let’s consider defining a macro for concatenating strings that can handle any number of input strings. If there are no inputs, the macro will produce an empty string. If there’s only one input string, it will simply return that string. For multiple inputs, the macro will create a new string that concatenates all the input strings. Let’s begin by defining this macro. Listing 15.25 shows the definition of the macro rule for the first case, when the macro is invoked with no arguments.

macro_rules! ...
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Publisher Resources

ISBN: 9781807785116