How is type checking implemented in Go without the need for explicit type declarations?

In the Go language, type checking and type inference for variables are implemented using the type inference mechanism, which allows the compiler to automatically determine the variable's type based on the assigned value.

For this, the := operator is used, which simultaneously declares and initializes a variable without explicitly specifying the type:

x := 42       // the compiler infers that x is an int
name := "Go" // the compiler infers that name is a string

Thus, Go allows writing more concise code while maintaining strict typing.

Important: this mechanism only works when declaring a new variable. If the variable is already declared, the usual assignment = should be used.