---
title: "SourceFunctionSpecification | JavaScript maps SDK"
description: "Documentation for MapTiler SDK"
---

> For AI agents: a documentation index is available at [/llms.txt](https://docs.maptiler.com/llms.txt). Markdown versions of all pages are available by appending .md to any URL.

# Type Alias SourceFunctionSpecification<T>

SourceFunctionSpecification:  
    | {  
        default?: [T](#t);  
        property: string;  
        stops: \[number, [T](#t)\]\[\];  
        type: "exponential";  
    }  
    | { default?: [T](#t); property: string; stops: \[number, [T](#t)\]\[\]; type: "interval" }  
    | {  
        default?: [T](#t);  
        property: string;  
        stops: \[string | number | boolean, [T](#t)\]\[\];  
        type: "categorical";  
    }  
    | { default?: [T](#t); property: string; type: "identity" }

#### Type Parameters

-   T