B. Expressions

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Feature	Status	Notes
Arithmetic (+, -, *, /, %)	✅	Binary ops via try_lower_expression_binary_ops.
Comparison (==, !=, <, >, <=, >=)	✅	Via try_lower_expression_comparisons.
Logical (&&, ||, !)	✅	Short-circuit evaluation.
Bitwise (&, |, ^, ~, <<, >>)	✅	Full bitwise support.
Unary (++, --, -, !)	✅	Pre/post increment/decrement.
Ternary (? :)	✅	ConditionalOperator lowered with labels.
Assignment (=, +=, -=, etc.)	✅	Compound assignments in assignments/compound.rs.
delete	✅	State vars, mapping entries, locals, array elements, struct fields.
Tuple expressions (a, b, c)	✅	Lowered to NeoVM arrays.
Tuple destructuring (a, b) = f()	⚠️	Supported. Some complex nested target forms may require intermediate locals.
Type casting	✅	Explicit casts between compatible types.
type(X).min / type(X).max	✅	Supported for integer types.
type(T).name	✅	Compile-time string constant.
type(I).interfaceId	✅	Computed from selector XOR of interface methods.
abi.encode(...)	⚠️	Supported in context of address.call/staticcall. Standalone use is limited.
abi.encodePacked(...)	⚠️	Same as abi.encode — used for Neo contract call encoding.
abi.encodeWithSignature(...)	⚠️	Low-level call payloads rewrite to Neo contract calls; standalone use approximates calldata as selector || abi.encode(args).
abi.encodeWithSelector(...)	⚠️	Low-level call payloads rewrite to Neo contract calls; standalone use approximates calldata as selector || abi.encode(args).
abi.encodeCall(...)	✅	Maps to StdLib.serialize.
abi.decode(...)	✅	Maps to StdLib.deserialize. Type tuple parsed from second argument.
Named function call args f({x: 1})	✅	Named args reordered to positional order at IR level.

Partial expression details

Tuple destructuring — Standard patterns like (uint a, uint b) = getValues() work. Deeply nested destructuring targets (e.g., destructuring into struct members or nested tuples in a single statement) may require the compiler to introduce intermediate locals.

abi.encode / abi.encodePacked / abi.encodeWithSignature / abi.encodeWithSelector — These functions are primarily designed for cross-contract call encoding on Neo, not for producing Ethereum-ABI-compatible byte sequences. When used as arguments to address.call() or address.staticcall(), the compiler rewrites them into Neo contract-call lowering. Standalone use now returns a Neo-side approximation: abi.encode* emits StdLib.serialize(...), while encodeWithSignature / encodeWithSelector emit selector || abi.encode(args). These byte sequences are useful on Neo, but not guaranteed to be EVM-identical raw calldata.

// ✅ Works — encoding for cross-contract call
address(target).call(abi.encodeWithSignature("transfer(address,uint256)", to, amount));

// ⚠️ Limited — standalone encoding may differ from EVM ABI
bytes memory encoded = abi.encode(a, b, c);
bytes memory payload = abi.encodeWithSignature("transfer(address,uint256)", to, amount);

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