emit

Documentation

Overview

Package emit implements low-level functions for Neo VM script creation.

This package is not intended to be used by applications directly, see smartcontract package for more convenient ways to create standard and well-known scripts. Use this package only if you can't create the script you need in any other way.

Index

• func Any(w *io.BinWriter, something any)
• func AppCall(w *io.BinWriter, scriptHash util.Uint160, operation string, ...)
• func AppCallNoArgs(w *io.BinWriter, scriptHash util.Uint160, operation string, ...)
• func Array(w *io.BinWriter, es ...any)
• func BigInt(w *io.BinWriter, n *big.Int)
• func Bool(w *io.BinWriter, ok bool)
• func Bytes(w *io.BinWriter, b []byte)
• func Call(w *io.BinWriter, op opcode.Opcode, label uint16)
• func CheckSig(w *io.BinWriter, key []byte)
• func Convertible(w *io.BinWriter, c stackitem.Convertible)
• func InitSlot(w *io.BinWriter, locals, args uint8)
• func Instruction(w *io.BinWriter, op opcode.Opcode, b []byte)
• func Int(w *io.BinWriter, i int64)
• func Jmp(w *io.BinWriter, op opcode.Opcode, label uint16)
• func Opcodes(w *io.BinWriter, ops ...opcode.Opcode)
• func StackItem(w *io.BinWriter, si stackitem.Item)
• func String(w *io.BinWriter, s string)
• func Syscall(w *io.BinWriter, api string)

Functions

func Any

func Any(w *io.BinWriter, something any)

Any emits element if supported. It accepts elements of the following types:

• int8, int16, int32, int64, int
• uint8, uint16, uint32, uint64, uint
• *big.Int
• string, []byte
• util.Uint160, *util.Uint160, util.Uint256, *util.Uint256
• bool
• stackitem.Convertible, stackitem.Item
• nil
• []any

errors.ErrUnsupported is returned for unsupported types.

func AppCall

func AppCall(w *io.BinWriter, scriptHash util.Uint160, operation string, f callflag.CallFlag, args ...any)

AppCall emits SYSCALL with System.Contract.Call parameter for given contract, operation, call flag and arguments.

func AppCallNoArgs

func AppCallNoArgs(w *io.BinWriter, scriptHash util.Uint160, operation string, f callflag.CallFlag)

AppCallNoArgs emits a call to the provided contract.

func Array

func Array(w *io.BinWriter, es ...any)

Array emits an array of elements to the given buffer. It accepts everything that Any accepts.

func BigInt

func BigInt(w *io.BinWriter, n *big.Int)

BigInt emits a big-integer to the given buffer.

func Bool

func Bool(w *io.BinWriter, ok bool)

Bool emits a bool type to the given buffer.

func Bytes

func Bytes(w *io.BinWriter, b []byte)

Bytes emits a byte array to the given buffer.

func Call

func Call(w *io.BinWriter, op opcode.Opcode, label uint16)

Call emits a call Instruction with the label to the given buffer.

func CheckSig

func CheckSig(w *io.BinWriter, key []byte)

CheckSig emits a single-key verification script using given []bytes as a key. It does not check for key correctness, so you can get an invalid script if the data passed is not really a public key.

func Convertible

func Convertible(w *io.BinWriter, c stackitem.Convertible)

Convertible converts provided stackitem.Convertible to the stackitem.Item and emits the item to the given buffer.

func InitSlot

func InitSlot(w *io.BinWriter, locals, args uint8)

InitSlot emits INITSLOT instruction with the specified size of locals/args slots.

func Instruction

func Instruction(w *io.BinWriter, op opcode.Opcode, b []byte)

Instruction emits a VM Instruction with data to the given buffer.

func Int

func Int(w *io.BinWriter, i int64)

Int emits an int type to the given buffer.

func Jmp

func Jmp(w *io.BinWriter, op opcode.Opcode, label uint16)

Jmp emits a jump Instruction along with the label to the given buffer.

func Opcodes

func Opcodes(w *io.BinWriter, ops ...opcode.Opcode)

Opcodes emits a single VM Instruction without arguments to the given buffer.

func StackItem

func StackItem(w *io.BinWriter, si stackitem.Item)

StackItem emits provided stackitem.Item to the given buffer. If it can't be emitted errors.ErrUnsupported is returned.

func String

func String(w *io.BinWriter, s string)

String emits a string to the given buffer.

func Syscall

func Syscall(w *io.BinWriter, api string)

Syscall emits the syscall API to the given buffer. Syscall API string cannot be 0.