How to modify SWIFT_MODULE_NAME?

Question

The title says it all. I've searched in the build settings for SWIFT_MODULE_NAME, and nothing came up. I've also searched online, and there are references to this name, but there is no information on how it is defined. Furthermore, I couldn't find any mention of SWIFT_MODULE_NAME in the Apple Docs.

I do know this: it is used in the "Objective-C Generated Interface Header Name" build setting, and can be viewed by double-clicking on the settings value:

$(SWIFT_MODULE_NAME)-Swift.h

It is used to bridge the gap between Objective-C and Swift, and appears only for projects that include Swift files, (along with Objective-C files I presume). As of this posting, Xcode 7.3 is the latest and greatest.

But, where is this value defined, and how do I modify it?

Dessiedessma

Have you checked out this doc: developer.apple.com/library/ios/documentation/Swift/Conceptual/… ? usually it is your product name. You can set change the value in "Product Bundle Identifier" in Build Settings. Note you can not override a product name in a Framework – Lammastide

Yes that's helpful, thanks. From that doc: "Xcode uses your product module name (PRODUCT_MODULE_NAME)—not your target name (TARGET_NAME)—when naming the Objective-C bridging header and the generated header for your Swift code." – Dessiedessma

Answer 1

The module name comes from the Product Module Name build setting:

The SWIFT_MODULE_NAME setting is apparently hidden, but you can see its derivation by looking at Xcode.app/Contents/PlugIns/Xcode3Core.ideplugin/Contents/SharedSupport/Developer/Library/Xcode/Plug-ins/XCLanguageSupport.xcplugin/Contents/Resources/Swift.xcspec:

...
{
    Name = "SWIFT_MODULE_NAME";
    Type = String;
    DefaultValue = "$(PRODUCT_MODULE_NAME)";
    CommandLineArgs = (
        "-module-name",
        "$(value)",
    );
},
...

Bellabelladonna

Thank you, that's it! I changed the PRODUCT_MODULE_NAME, and the SWIFT_MODULE_NAME was updated! – Dessiedessma

Oh my, 4 hours looking for this - debated the concept of retirement. Xcode Version 9.4 (9F1027a) had filled it blank from a fresh swift project create 3 days ago. I will post a possible bug. ouch! don't forget #import "MsbHrv-Swift.h" in the .m, for every function on swift object that your accessing put the "@objc" in front of the declaration in the .swift file, and make sure this SWIFT_MODULE_NAME is set in the PRODUCT_MODULE_NAME. OR just build everything in swift, be happy, and pet puppies to calm your day. – Prodigious

Please note that Product Module Name defaults to using $(PRODUCT_NAME:c99extidentifier) so the best place to change this is to ensure that you set PRODUCT_NAME or "Product Name" to a value and all will update accordingly. – Jhvh

To follow up on Dino's observation: There's yet another step, because PRODUCT_NAME is defined as $(TARGET_NAME). But... it dead-ends there. I can't find TARGET_NAME in any of the settings; maybe Xcode only shows it in the project navigator (left pane). One more thing: If your project or product name is hyphenated, Xcode will replace the hyphen with an underscore. This will cause builds to fail if you explicitly refer to the $(SWIFT_MODULE_NAME)-Swift.h file's expected name anywhere. – Jutland

Answer 2

SWIFT_MODULE_NAME, PRODUCT_MODULE_NAME, PRODUCT_NAME, EXECUTABLE_NAME

Default values:

EXECUTABLE_NAME = $EXECUTABLE_PREFIX$PRODUCT_NAME$EXECUTABLE_SUFFIX
SWIFT_OBJC_INTERFACE_HEADER_NAME = $(SWIFT_MODULE_NAME) 

SWIFT_MODULE_NAME = $(PRODUCT_MODULE_NAME)
PRODUCT_MODULE_NAME = $(PRODUCT_NAME:c99extidentifier)
PRODUCT_NAME = $(TARGET_NAME:c99extidentifier)

Observation:

SWIFT_MODULE_NAME == PRODUCT_MODULE_NAME

c99extidentifier

Xcode is able to substitute a value of variable c99extidentifier identifier which supports extended characters from C99

//for example
PRODUCT_NAME = My Framework
PRODUCT_MODULE_NAME = $(PRODUCT_NAME:c99extidentifier) = My_Framework

EXECUTABLE_NAME name of binary

Product Module Name(PRODUCT_MODULE_NAME) determines how the import statement will look like. For example when you are creating a Library or a Framework.

Using:

//Objective-C
@import module_name; 

//Swift
import module_name 

Product Name(PRODUCT_NAME) determines the name of binary. E.g. MyFramework.framework

[TARGET_NAME]

Rule is:

SWIFT_MODULE_NAME should equal to PRODUCT_MODULE_NAME

[Custom .modulemap]

Barkentine

Answer 3

Go to build Settings and click + next to 'Levels'. See :

replace NEW_SETTING as SWIFT_MODULE_NAME for the name of the setting, and whatever is the module name for .h file (No spaces, please) goes on the right.

Extrasystole

Hit the plus sign for add user defined settings was the part i missed at first. – Bethea

Added SWIFT_MODULE_NAME and fixed my unit tests on XCode 9 because our module name has a "-" in it. Thanks. – Specific

Answer 4

Have you checked out this doc: developer.apple.com/library/ios/documentation/Swift/Conceptual/… ? usually it is your product name. You can set change the value in "Product Bundle Identifier" in Build Settings. Note you can not override a product name in a Framework

See the screenshot:

Lammastide