modern-move-syntax

modern-move-syntax

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Overview

The Move 2024 edition introduced method syntax and several convenience features. AI agents frequently fall back to pre-2024 function-call patterns from training data. This skill covers every modern syntax pattern.

All patterns sourced from https://move-book.com/guides/code-quality-checklist

Method Syntax for Common Operations

Use method-call syntax (dot notation) instead of module function calls.

Coin and Balance

// WRONG — legacy function-call syntax
let value = coin::value(&payment);
let balance = coin::into_balance(payment);
balance::join(&mut pool.reserve, balance);
let coin = coin::from_balance(balance::split(&mut pool.reserve, amount), ctx);

// CORRECT — method syntax
let value = payment.value();
let balance = payment.into_balance();
pool.reserve.join(balance);
let coin = coin::from_balance(pool.reserve.split(amount), ctx);

// BEST — chained method calls
let balance = payment.split(amount, ctx).into_balance();

TxContext

// WRONG
tx_context::sender(ctx)

// CORRECT
ctx.sender()

UID and Object

// WRONG
object::delete(id);

// CORRECT
id.delete();

String Literals

Use quoted string literals directly, not std::string::utf8() or byte-string conversion.

// WRONG
use std::string;
let s = string::utf8(b"hello");

// ALSO WRONG — unnecessary conversion
let s = b"hello".to_string();

// CORRECT — direct string literals (2024 edition)
let s = "hello";                    // String (UTF-8)
let ascii = "hello";                // also works for ASCII strings
let s = b"hello".to_string();      // still valid but prefer quoted form
let ascii = b"hello".to_ascii_string(); // explicit ASCII when needed

Vector Literals and Methods

Use vector literal syntax and method calls instead of module functions.