Module interpolation 

Interpolation parsing per ADR-011

Parses interpolation expressions like:

• ${env:VAR} - resolver with argument
• ${env:VAR,default} - resolver with default
• ${path.to.value} - self-reference
• ${.sibling} - relative self-reference
• \${escaped} - escaped (literal) interpolation
• ${env:VAR,${env:OTHER,fallback}} - nested interpolations

Structs

InterpolationParser

Parser for interpolation expressions

Enums

Interpolation

A parsed interpolation expression

InterpolationArg

An argument to an interpolation (may itself contain interpolations)

Functions

contains_interpolation

Check if a string contains any interpolation expressions (unescaped ${…})

needs_processing

Check if a string needs processing (has interpolations OR escape sequences)

parse

Parse an interpolation string