use fmt

Formatted output functions using printf-style format specifiers.

Format specifiers

Modifiers

• Width: "%5d" pads to 5 characters
• Precision: "%.2f" limits to 2 decimal places
• Zero-pad: "%05d" pads with zeros
• Left-align: "%-5d" left-aligns within width
• Sign: "%+d" always shows sign

use fmt

fn main() {
    42 "%d" fmt::printf nl             // 42
    255 "%x" fmt::printf nl            // ff
    3.14159 "%.2f" fmt::printf nl      // 3.14
    42 "%05d" fmt::printf nl           // 00042
    65 "%c" fmt::printf nl             // A
    "test" 42 "%s = %d" fmt::printf nl // test = 42
}

Arguments are pushed onto the stack before the format string, in the order they appear in the format string.

Functions

fn printf

Print formatted output to stdout.

Signature: (format:str -- )

Example:

"world" "Hello %s\n" fmt::printf  // Hello world

fn sprintf

Format a string with printf-style specifiers.

Signature: (format:str -- result:str)

Example:

"world" "Hello %s\n" fmt::sprintf  // "Hello world\n"