expansion

func Expand ¶

func Expand(input string, mapping func(string) string) string

Expand replaces variable references in the input string according to the expansion spec using the given mapping function to resolve the values of variables.

Escape semantics:

• $(VAR_NAME) is replaced with the mapped value of VAR_NAME.
• $$(VAR_NAME) is replaced with the literal string $(VAR_NAME).
• References to undefined variables are left as-is.

func MappingFuncFor ¶

func MappingFuncFor(context ...map[string]string) func(string) string

MappingFuncFor returns a mapping function for use with Expand that implements the expansion semantics defined in the expansion spec; it returns the input string wrapped in the expansion syntax if no mapping for the input is found.