Text Placeholders Overview

When text contains named values supplied at runtime, a replacer connects each placeholder to a source and applies any requested filters. These topics show how to start with the built-in providers, then adapt the workflow to your application.

Completing Text with Placeholders introduces replacement, syntax, and error handling. Using Built-in Placeholder Sources explains how the built-in var and env sources obtain values. Transforming Placeholder Text with Built-in Filters covers filters that clean, select, escape, and validate those values.

When values come from an application service or need a domain-specific transformation, Providing Your Own Placeholder Values and Filters shows how to write and register providers. Choosing Placeholder Syntax for Your Text explains frames, separators, escaping, and safe use in layered text formats.