quote

Builds generated code inside a macro: quote items|expr|stmts|type { template }.

The template is Coil source with holes: ${e} splices an expression, name, type or Code, and $(xs),* splices a Vec<Code> with a separator. The result is a Code value. Names bound inside the template are renamed so they cannot clash with the caller’s. Contextual: quote(x) stays a call.

use macro::{Expr, Code};

macro twice(Expr e) -> Code {
    return quote stmts {
        ${e};
        ${e};
    };
}

See also#

• Vec
• fn: Declares a function, a method, or (written in an expression) an anonymous function.
• let: Declares a mutable local variable.
• const: Declares a binding that cannot be reassigned: a local, a module constant, or a class field that is set only by new.
• static: Declares a module-level or class-level slot shared by the whole program, or a method without self.
• readonly: A read-only view of a value: nothing reachable through it can be changed.
• if: Runs a block when a bool condition is true.
• else: Introduces the branch of an if that runs when its condition is false (or its pattern does not match).