enterCalc

EnterCalc Keyboard Actions and Context Matrix

This document defines keyboard behavior currently implemented in EnterCalc for iOS and macOS.

Sources:

• iOS key routing: apple/src/iOS/EnterCalcIOSApp.swift
• macOS key routing: apple/src/macOS/CalculatorWindowView.swift

Global Notes

• End is treated like Escape for calculator state in base/direct-edit contexts.
• Backspace and Forward Delete are intentionally treated the same for operand deletion in base/direct-edit contexts.

Keyboard Matrix

Key	Base	Direct edit	Rounding overlay	History overlay
Insert	Enter direct edit; caret to trailing boundary	Already in direct edit; no extra action	Blocked while overlay is active	Blocked while overlay is active
Left Arrow	Move display caret left (activates direct edit if possible)	Move display caret left	Decrease rounding precision step	Suppressed
Right Arrow	Move display caret right (activates direct edit if possible)	Move display caret right	Increase rounding precision step	Suppressed
Down Arrow	Open rounding overlay	Open rounding overlay	No-op (consumed)	Suppressed
Up Arrow	No mapped action	No mapped action	Close rounding overlay	Suppressed
Escape	Clear all	Exit direct edit	Remove rounding and close overlay	Close overlay
End	Clear all	Exit direct edit	Close overlay	Close overlay
Backspace	Delete one char/digit via model backspace	Delete one char/digit before caret	Remove rounding and close overlay	Close overlay
Forward Delete	Delete one char/digit via model backspace	Delete one char/digit before caret	Remove rounding and close overlay	Clear history and close overlay
Return / Enter / Keypad Enter	Evaluate	Exit direct edit	Close overlay	Close overlay
Digits 0-9	Input digit	Insert at display caret	Not handled here	Suppressed
Decimal .	Input decimal separator	Insert decimal at display caret	Not handled here	Suppressed
+ - * /	Set operator	Set operator (exits direct edit in model flow)	Not handled here	Suppressed
%	Apply percent	Apply percent	Not handled here	Suppressed
( and )	Input parentheses	Input parentheses	Not handled here	Suppressed
=	Evaluate	Evaluate path applies; direct edit Enter key exits edit	Not handled here	Suppressed
Currency symbols ($, €, £, etc.)	Activate currency input mode with symbol	Same behavior at caret position	Not handled here	Suppressed

Platform Notes

• iOS and macOS use the same keyboard actions in all contexts.
• Insert key detection differs by platform implementation details:
  • iOS accepts HID usages 0x49 (Insert) and 0x75 (Help), plus function-character U+F727.
  • macOS accepts keyCode 114, plus function-character U+F727.
• macOS additionally maps physical keypad keyCodes for digits/operators/decimal/evaluate. iOS receives these through hardware key events and characters.
• Control-modified keys are not handled by EnterCalc keyboard routing and return not-handled.

Command Shortcuts

• Cmd + Backspace: clear all.
• Cmd + Forward Delete: clear all.
• Cmd + C: copy current result.
• Cmd + V: paste into calculator.
• Cmd + Z: undo.
• Cmd + Shift + Z: redo.
• Cmd + Y: redo.

Overlay Priority Rules

• History overlay has highest keyboard suppression behavior for calculator input.
• Rounding overlay handles its own close/remove/adjust keys before base key routing.
• Insert only enters direct edit when no overlay is active.

This site is open source. Improve this page.