Macros Introduction

Development Macros
1

I'm using

$ swift -v
Swift version 5.9-dev (LLVM 84aca0981812b32, Swift 8790101221df99d)
Target: x86_64-unknown-linux-gnu

and I wanted to experiment with the new feature Macros but i keep getting this errors

error: macros are an experimental feature that is not enabled
@freestanding(expression) public macro stringify<T>(_ value: T) -> (T, String) = #externalMacro(module: "Macros", type: "StringifyMacro")

and this one too

warning: external macro implementation type 'Macros.StringifyMacro' could not be found for macro 'stringify'; the type must be public and provided via '-load-plugin-library'

and even tried the enable-experimental-feature flag and still nothing

$ swift build  -Xswiftc='-enable-experimental-feature macros'
Building for debugging...
error: unknown argument: '-enable-experimental-feature macros'
error: unknown argument: '-enable-experimental-feature macros'

Can anyone help me out?

File organization:

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2

I missed this message before, sorry.

Experimental feature names are case-sensitive, so this would need to be spelled --enable-experimental-feature Macros. However, if you grab a newer snapshot from swift.org you won't need the flag at all.

The easiest way to get started is generally to use the macro examples project.

Doug

3

I've downloaded the latest development swift version but a new error pops up

error: macros are not supported in this compiler
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