Print

Console output utilities.

Module: Std::Io

Summary

import Std::Io::{ Print, PrintLine };
import Std::Format;

func Main() -> int {
    let score: int32 = 9001;
    let name  = String::From("Alex");

    PrintLine("Player: {}", name);
    PrintLine("Score:  {}", score);
    Print("Status: ");
    PrintLine("active");

    return 0;
}

Description

The Std::Io module provides console output functionality for strings, primitive types, and formatted text.

All supported primitive types can be printed directly. Internally, values are converted to strings before being written to the console.

The module supports:

• Primitive numeric types
• Boolean types
• Character types
• Strings
• Formatted output using Display

---

Print

Writes a value to standard output without appending a newline.

Overloads

Primitive Types

Print(value: int8)
Print(value: int16)
Print(value: int32)
Print(value: int64)

Print(value: int)

Print(value: uint8)
Print(value: uint16)
Print(value: uint32)
Print(value: uint64)

Print(value: float32)
Print(value: float64)

Print(value: bool8)
Print(value: bool16)
Print(value: bool32)
Print(value: bool)

Print(value: char8)
Print(value: char16)
Print(value: char32)
Print(value: char)

Strings

Print(string: *const char8, length: uint)
Print(string: *const char16, length: uint)

Print(string: char8[])
Print(string: char16[])

Print(string: String)

Formatted Output

Print(
    format: char8[],
    args: Display...
)

Formats the arguments using Format() and writes the result to standard output.

Example

Print(
    "Hello, {}!",
    String::From("Alex")
);

Output:

Hello, Alex!

---

PrintLine

Writes a value to standard output and appends a newline.

Overloads

Newline Only

PrintLine()

Writes a line terminator.

Primitive Types

PrintLine(value: int8)
PrintLine(value: int16)
PrintLine(value: int32)
PrintLine(value: int64)

PrintLine(value: int)

PrintLine(value: uint8)
PrintLine(value: uint16)
PrintLine(value: uint32)
PrintLine(value: uint64)

PrintLine(value: float32)
PrintLine(value: float64)

PrintLine(value: bool8)
PrintLine(value: bool16)
PrintLine(value: bool32)
PrintLine(value: bool)

PrintLine(value: char8)
PrintLine(value: char16)
PrintLine(value: char32)
PrintLine(value: char)

Strings

PrintLine(string: *const char8, length: uint)
PrintLine(string: *const char16, length: uint)

PrintLine(string: char8[])
PrintLine(string: char16[])

PrintLine(string: String)

Formatted Output

PrintLine(
    format: char8[],
    args: Display...
)

Formats the arguments using Format(), writes the result, and appends a newline.

Example

PrintLine(
    "{} scored {} points",
    playerName,
    score
);

Output:

Alex scored 42 points

---

Notes

• Primitive values are converted to strings automatically.
• Formatted output uses Format().
• Values supplied to formatted output must implement Display.
• Print() does not append a newline.
• PrintLine() always appends a newline.

---

Platform Notes

Linux / BSD / Illumos

• UTF-8 text is written directly to standard output via the write syscall.
• Linux: SYS_WRITE = 1 (negative errno).
• BSD / Illumos: SYS_WRITE = 4 (positive errno).

Windows

• UTF-8 text is converted to UTF-16 before being written to the console.
• UTF-16 output is written using the Windows console API.

Output Length Limit

Strings longer than 4096 characters currently cause a fatal error when printed. Attempting to print a longer UTF-8 string will terminate the program with:

Fatal("string is too long to print")

This limitation applies to:

Print(...)
PrintLine(...)

when the underlying string exceeds 4096 characters.

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