package vm import ( "fmt" "github.com/ethereum/go-ethereum/params" ) func makeStackFunc(pop, diff int) stackValidationFunc { return func(stack *Stack) error { if err := stack.require(pop); err != nil { return err } if int64(stack.len()+diff) > params.StackLimit.Int64() { return fmt.Errorf("stack limit reached %d (%d)", stack.len(), params.StackLimit) } return nil } } func makeDupStackFunc(n int) stackValidationFunc { return makeStackFunc(n, 1) } func makeSwapStackFunc(n int) stackValidationFunc { return makeStackFunc(n, 0) }