StringResolver

A small, standalone module of plain functions (no class, no hooks) that recursively walks a value and replaces {{binding.path}} references and @[ expression ]@ blocks with their resolved values.

Key Files

• core/player/src/string-resolver/index.ts — the entire module

What It Does

The module exports four functions:

• resolveDataRefs(val, options) — the main entry point. Recursively walks any value — string, object, or array — via an internal traverseObject, resolving refs in every string it finds and leaving everything else untouched.
• resolveDataRefsInString(val, options) — resolves both expressions and {{binding}} references within a single string.
• resolveExpressionsInString(val, options) — finds @[ ... ]@ blocks and replaces each with the result of options.evaluate(...).
• findNextExp(str) — finds the start/end offsets of the next {{ ... }} reference in a string.

options.model is a DataModelWithParser (or false to skip binding resolution) and options.evaluate is an expression-evaluation function (or false to skip expression resolution) — both are supplied by the caller, not owned by this module.

Balanced-Brace Handling

Bindings can themselves be nested, e.g. {{foo.{{bar}}.baz}}, so a naive “find the first }}” would break. findNextExp instead scans forward counting opens and closes: every time it sees another {{ before the next }}, it increments a counter instead of stopping, and only returns once the counter unwinds back to zero. This lets the resolver correctly find the matching closing }} for the opening one it started at, even with nested references in between.

Type-Preserving Short-Circuit

If a string is entirely a single reference — nothing before or after it — the resolved value keeps its original type instead of being stringified. Both resolveExpressionsInString and resolveDataRefsInString check for this explicitly: when the match spans the whole input string and the resolved value isn’t itself a string, they return that value directly rather than splicing it into a string.

For example, given count: 42 in the data model, the string "{{count}}" resolves to the number 42, not the string "42". But "Count: {{count}}" resolves to the string "Count: 42", since the reference isn’t the entire string. The same rule applies to @[ expr ]@ blocks.

This module has no plugin hooks — it’s a set of plain functions invoked directly by StringResolverPlugin during view resolution, not a tapable class.

Relationship to Other Subsystems

• View Plugins — see its StringResolverPlugin subsection; that plugin (core/player/src/view/plugins/string-resolver.ts) is the main caller of resolveDataRefs during node resolution, and is also referenced in the “incremental resolve” step of What Happens When Data Changes.
• Data & Expressions — the authoring-level explanation of {{}} and @[]@ syntax; this page covers how those references are resolved at runtime.