Vocabulary

Every value EscposPrinter accepts (justification, print modes, barcode types, etc.) has its own type under Derafu\Escpos\Enum\* or Derafu\Escpos\Constant\*. You never need to import anything from Mike42\Escpos\* to call any method.

These values are not arbitrary numbers chosen by this library. They are the ESC/POS protocol itself — the bytes a thermal printer actually expects, defined by the standard and shared by every ESC/POS library regardless of language. That is why they are safe to hardcode here instead of referencing the underlying library’s constants: they would not change even if the underlying library were replaced.

Enum vs. constant

• Enums (Derafu\Escpos\Enum\*) are used when the values are a mutually exclusive choice — you pick exactly one (e.g. left, center or right justification).
• Constants (Derafu\Escpos\Constant\*) are used when the values are independent bits meant to be combined with | (e.g. font + emphasized + double width at the same time). An enum would force unwrapping ->value on every term just to combine them, and the combined result would no longer be the enum type anyway — a plain int constant says what it is more honestly.

Enums

The “vocabulary only” enums exist because they are a small, closed set defined by the protocol — completing them costs nothing and keeps this package generic instead of shaped only around what its first consumer needed. They are ready for the day a setFont(), setColor(), setUnderline(), setBarcodeTextPosition() or qrCode() method is added to EscposPrinter, without needing new vocabulary at that point.

use Derafu\Escpos\Enum\Justification;

$printer->setJustification(Justification::Center);

Constants (bitmask flags)

use Derafu\Escpos\Constant\PrintMode;

// Combine flags with a plain bitwise OR.
$printer->selectPrintMode(PrintMode::FONT_B | PrintMode::EMPHASIZED);

What is deliberately not vocabulary

A few things found in mike42/escpos-php are not mapped, on purpose:

• Status request codes and raw control bytes (STATUS_*, ESC, GS, LF, …): these are not parameters of any command a caller chooses — they are either internal bytes the underlying library uses to build each command, or (for STATUS_*) not used by any method in the vendored version at all. Mapping them would be vocabulary for a feature that does not exist.
• Character tables / code pages: unlike everything above, the correct table number is not a fixed protocol value — it depends on the specific printer’s capability profile. This is a known open item, not yet designed.