Modifiers

Modifiers are functions that shorten the path of data transformation.

Boolean

Compare values and return true or false. Combine with conditionals to branch template output.

Modifier	Description
`eq`	Eq returns true if the value equals the given parameter.
`gt`	Gt returns true if the numeric value is greater than the threshold.
`gte`	Gte returns true if the numeric value is greater than or equal to the threshold.
`not`	Not inverts the truthiness of the value.

Work with arrays and maps — sort, filter, find, extract keys, and reshape data.

Modifier	Description
`filter`	Filter returns a subset of a slice where a nested field matches a value.
`find`	Find returns the first element in a slice or map where a field equals the given value.
`first`	First returns the first character of a string or the first element of a slice.
`has`	Has returns true if the slice or map contains the given value.
`is`	Is returns true if the value equals any of the given parameters.
`key`	Key extracts a value from a map or slice by key path or index.
`last`	Last returns the last character of a string or the last element of a slice.
`map`	Map converts a slice of maps into a map keyed by the given field's string value.
`merge`	Merge converts a slice of maps into a map keyed by the given field's string value.
`sort`	Sort sorts a slice in ascending or descending order.
`wrap`	Wrap wraps the value in a map under the given key.

Serialize and deserialize between Go values, JSON, and YAML.

Modifier	Description
`from`	From parses the string value as the given format and returns the parsed result.
`json`	JSON serializes the value to a JSON string.
`markdown`	Markdown converts an HTML string to Markdown.
`yaml`	YAML serializes or parses a value as YAML.

Extract and manipulate path components — directory, filename, and extension.

Modifier	Description
`dirname`	Dirname returns the directory portion of a file path.
`ext`	FilenameExt returns the file extension without the leading dot.
`ext-dot`	FilenameExtDot returns the file extension including the leading dot.
`ext-prepend`	FilenamePrependExt inserts an additional extension before the existing file extension.
`ext-trim`	FilenameTrimExt returns the file path without its extension.
`filename`	Filename returns the base file name from a path, including the extension.

Convert between currency units and denominations.

Modifier	Description
`currency`	Currency converts a numeric value between currency units by applying a unit multiplier ratio.

Manipulate strings — trim whitespace, change case, split, join, slugify, and more.

Modifier	Description
`concat`	Concat appends one or more strings to the value.
`join`	Join combines an array of strings into a single string with a separator.
`lines`	Lines splits a string or byte slice into an array of lines.
`lower`	ToLower converts a string to lowercase.
`replace`	Replace replaces all occurrences of a substring within the string value.
`replace_pattern`	ReplacePattern replaces all regex matches within the string value.
`reverse`	Reverse reverses the characters in a string.
`sexy`	Sexy returns a bear ASCII art.
`shorten`	Shorten truncates a string to the given maximum character length.
`slug`	Slug converts a string to a URL-friendly slug.
`split`	Split splits a string into an array using a separator.
`title`	Title converts a hyphen-separated slug into a title-cased string.
`title_model`	ModelTitle formats an AI model identifier into a human-readable title.
`trim`	Trim removes leading and trailing whitespace, or the given character set.
`trim-prefix`	TrimPrefix removes a leading prefix string or leading whitespace from the value.
`trim-suffix`	TrimSuffix removes a trailing suffix string or trailing whitespace from the value.
`upper`	ToUpper converts a string to uppercase.

General-purpose modifiers — defaults, lengths, line numbers, and date formatting.

Modifier	Description
`default`	Default returns the fallback value if the input is nil or an empty string.
`format`	Format formats a time.
`length`	Length returns the number of characters in a string or bytes in a byte slice.
`line-numbers`	LineNumbers prepends each line of the string with its zero-based line number.

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