Lesson 47 of 55
15 mins readPython Template Literal Types and Key Remapping
In Plain English
Template literal types build on string literal types to produce combinations of string patterns at compile time. In mapped types, the as clause allows renaming property keys.
Core Rules to Remember

Template Literal Types: `prefix_${StringUnion}` generates all combinations of prefixed literal types.

Key Remapping (as): Renames property keys within mapped types (e.g. adding get/set prefixes).
Live Interactive Example
Hit Run Code to see it liveString Metaprogramming and Getter Generation
Python 3.12
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Output Console
Click "Run Code" to view the rendered output.
How it works: Template literal types allow compile-time generation of prefixed string keys and method signatures.
Your Turn: Micro Challenge
No pressure! Edit the starter code below and test your solution with instant feedback.
Micro Exercise
Build CRUD Action Names
Define type Entity = "User" | "Post".
Define type Action = "Create" | "Delete".
Create type Command = `${Action}${Entity}`.
Assign const cmd: Command = "CreateUser" and print cmd.
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Sandbox Output
Click "Run & Check" to test your solution.
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