Inline Constants

Inline C and C++ constants directly at the usage site.

Inline Constants replaces supported #define, const, and constexpr usages with their resolved values so you can simplify code without manually copying expressions around.

Features

• Inline object-like macros such as #define Padding 24
• Inline simple function-like macros such as #define ADD_ONE(x) ((x) + 1)
• Inline const and constexpr variables with initializers
• Works with same-file and cross-file definitions when a definition provider can resolve the symbol
• Available from the Command Palette, editor context menu, and code actions
• Optional hover action for quick inline-at-cursor workflow

Example

Before:

constexpr int emptyStatePadding = 24;

int render() {
	return emptyStatePadding;
}

After:

constexpr int emptyStatePadding = 24;

int render() {
	return 24;
}

Function-like macros are expanded with the call-site arguments:

#define ADD_ONE(x) ((x) + 1)

int render(int value) {
	return ADD_ONE(value);
}

becomes:

int render(int value) {
	return ((value) + 1);
}

Supported Languages

• C
• C++
• CUDA C++
• Objective-C
• Objective-C++

Requirements

Inline Constants relies on a definition provider to locate the original symbol declaration.

For best results, install a C/C++ language extension that provides definition resolution, such as:

• Microsoft C/C++
• clangd

Usage

Place the cursor on a supported constant usage, then use one of these entry points:

• Run Inline Constants: Inline Constant from the Command Palette
• Right-click and choose Inline Constant
• Trigger a code action or refactor at the cursor
• Hover the symbol and click the inline action when hover mode is enabled

The action is only offered on inlineable usages. It is not offered on the original definition.

Extension Settings

This extension contributes the following settings:

• inlineConstants.clickBehavior: Controls the optional click workflow. hoverLink shows an inline action in the hover tooltip. disabled turns off click-driven inlining.
• inlineConstants.parenthesizeExpressions: Wraps inserted expressions in parentheses when they contain top-level operators.

Current Limitations

• Function-like macros that use variadic arguments, stringizing, or token pasting are ignored
• Malformed declarations and unsupported initializer forms are ignored
• Hover actions only appear when the symbol at the cursor can actually be inlined
• Replacement quality depends on the underlying definition provider being able to resolve the symbol correctly

Development

npm install
npm run compile
npm test

Press F5 in VS Code to launch the extension development host.