Builtin Processor Reference

Processors transform rendered strings. Write them after a rule reference with |; a pipeline runs left to right. For example, {name | trim | capitalize} trims before changing case. They also work in binding statements, such as {% hero:name | uppercase %}. Unknown names fail at render time with UnknownProcessor.

The examples below show processor input and output, independent of config string escaping.

capitalize changes the first character to uppercase and lowercases the remaining characters. titlecase capitalizes words separated by whitespace. sentence changes only the first alphabetic character and preserves the rest. slug lowercases text, removes apostrophes, and joins runs of other non-alphanumeric characters with hyphens.

article uses English pronunciation heuristics (an hour, a user) and prefixes the original string. Use trim | article if leading or trailing whitespace should be removed first. The inflection processors use regular spelling rules and a set of common irregular English words. They are not full natural-language parsers. past_tense, present_participle, pluralize, singularize, possessive, and ordinal require exactly one token; blank or multi-word input returns ProcessorError. ordinal additionally requires an integer. These processors preserve surrounding whitespace. quote wraps text in ASCII double quotes and escapes embedded quotes and backslashes; it does not convert a complete object to JSON.