Macro solana_sdk::msg
source · macro_rules! msg { ($msg:expr) => { ... }; ($($arg:tt)*) => { ... }; }
Expand description
Print a message to the log.
Supports simple strings as well as Rust format strings. When passed a
single expression it will be passed directly to sol_log
. The expression
must have type &str
, and is typically used for logging static strings.
When passed something other than an expression, particularly
a sequence of expressions, the tokens will be passed through the
format!
macro before being logged with sol_log
.
Note that Rust’s formatting machinery is relatively CPU-intensive for constrained environments like the Safecoin VM.
Examples
use solana_program::msg;
// The fast form
msg!("verifying multisig");
// With formatting
let err = "not enough signers";
msg!("multisig failed: {}", err);