Type literals

February 15, 2023

After a long-winded post yesterday, here’s a shorter one to breeze through…


… A type may also be specified using a type literal, which composes a type from existing types.

Type      = TypeName [ TypeArgs ] | TypeLit | "(" Type ")" .
TypeName  = identifier | QualifiedIdent .
TypeArgs  = "[" TypeList [ "," ] "]" .
TypeList  = Type { "," Type } .
TypeLit   = ArrayType | StructType | PointerType | FunctionType | InterfaceType |
            SliceType | MapType | ChannelType .

You’ve already seen these. []byte, *string and Struct { Name string; Age int } are all examples of type literals. There are many more type literals for specific types, which we’ll get to in the coming days.

We’re also skipping over TypeArgs and TypeList, which are related to generic types, for the time being.

Quotes from The Go Programming Language Specification, Version of January 19, 2023

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