Libraries

Back to Devpack Overview

Neo.sol (542 lines)

High-level blockchain integration library. Wraps Syscalls and NativeCalls into a convenient API:

Category	Functions
Block info	getCurrentBlock(), getBlockByIndex(), getBlockHeight(), getBlockTime()
Transactions	getTransaction(), getTransactionHeight()
Account/balance	NEO and GAS balance queries via NativeCalls
Cryptographic	Signature verification, hash functions (delegates to Syscalls CryptoLib)
Contract mgmt	Call, deploy, query contracts
Network	Governance, committee, validators
Gas	Fee calculations, gas management utilities

using Neo for *;

(uint256 index, bytes32 hash, uint256 timestamp, bytes32 merkle) = Neo.getCurrentBlock();
uint256 height = Neo.getBlockHeight();

Storage.sol (852 lines)

Advanced storage operations built on top of Syscalls storage syscalls:

Category	Functions
Context	getContext(), getReadOnlyContext(), asReadOnly()
Basic CRUD	put(), get(), remove(), exists()
Local storage	putLocal(), getLocal(), removeLocal()
Iterators	find(), findLocal(), findValues(), findKeys(), findLocalValues(), findLocalKeys()
Counting	count() — count entries matching a prefix
Batch ops	Batch put/remove (max 100 per batch)
Key derivation	Mapping keys, array keys, nested keys
Typed accessors	uint256, address, string, bool typed get/put
Secure storage	Checksum validation
Expiration	TTL-based storage entries

using Storage for *;

// Basic operations
Storage.put("owner", abi.encode(msg.sender));
bytes memory data = Storage.get("owner");
bool hasKey = Storage.exists("owner");

// Iterator-based prefix scan
bytes[] memory allValues = Storage.findValues("token:");
bytes[] memory allKeys = Storage.findKeys("token:");

// Local storage (contract-private, not visible to other contracts)
Storage.putLocal("internal_state", abi.encode(42));

Local vs Global Storage

put()/get() use the contract's global storage context. putLocal()/getLocal() use a local context that is private to the contract and cannot be read by other contracts via System.Storage.GetReadOnlyContext.

Runtime.sol (695 lines)

Runtime services and utilities (currently supported as compiler intrinsics):

Category	Functions
Events	notify(), notifyIndexed()
Witness	checkWitness(), requireWitness(), checkAnyWitness(), checkAllWitnesses(), checkMultiSigWitness()
Runtime context	gasLeft(), getTime(), getTrigger(), getInvocationCounter(), getCurrentSigners()
Contract context	getCallFlags(), getScriptContainer(), loadScript(), getExecutingScriptHash(), getCallingScriptHash(), getEntryScriptHash()
Platform	getNetwork(), getPlatform(), getAddressVersion(), getRandom()
Logging	log(), burnGas(), initializeServices()

using Runtime for *;

// Witness verification
bool hasWitness = Runtime.checkWitness(msg.sender);
require(hasWitness, "invalid witness");

// Gas management
uint256 remaining = Runtime.gasLeft();
Runtime.burnGas(1000000); // burn 0.01 GAS

Runtime Intrinsic Coverage

Runtime.sol includes callback-oriented convenience helpers that are not compiler intrinsics in neo-devpack-solidity. Calls to optimizeGasUsage, executeIfGasAvailable, and tryWithFallback are currently rejected at compile time because NeoVM does not support first-class internal function callbacks. Use inline logic (gasLeft guards and try/catch) instead.