go-pat

pattern matcher for go

import the match interface

import "github.com/fredim/go-pat/m"

build cases

matchCases := m.BuildCases(pat1, func1, pat2, func2, ...)

the arguments to the function depend on the exported values from the patterns

"string() as s", func(s string) string { return "got a string!" },

primitives are simple tokens with values in parantheses

"int(123)" matches an integer 123

structs are tokens with members in braces

"MyStruct{Member:value}"

Useful Members need to be Exported (Capitalized) to be able to use in funcs

"MyStruct{Member:val}", func(val MemberType) string { ... }

value can be a sub structure, as well

"MyStruct{Member:InnerStruct{}}"

the as keyword assigns a argument name to the match

"MyStruct{Member:InnerStruct{}} as ms", func(ms MyStruct) string { .. }

all funcs need to have the same return value

var matchFn func() string

Finally, execute the match, and provide a func pointer

matchCases.Match(obj, &matchFn)

Match will reassign the matchFn to the return value, so it can be invoked without arguments

return matchFn()

done!