Syntax Highlighting

Moonriver provides real-time syntax highlighting as you type commands.

Color Coding

Different command types are highlighted with distinct colors:

G-code Commands

Bright Green - Standard G-code commands

> G28
> M105
> G0 X100 Y100 Z10

Klipper Macros

Bright Cyan - User-defined Klipper macros

> PRINT_START
> BED_MESH_CALIBRATE
> SCREWS_TILT_CALCULATE

Unknown Commands

White - Unrecognized commands

> UNKNOWN_COMMAND

Response Coloring

Responses from the printer are also color-coded:

Success Messages

Green - Successful responses, "ok" messages

ok
// Homing complete

Information

Cyan - Normal informational messages

T:200.5 /200.0 B:60.2 /60.0
// Current position: X:100.0 Y:100.0 Z:10.0

Warnings

Yellow - Warning messages, comments starting with "//"

// Warning: Temperature variance detected
!! Endstop not triggered

Errors

Red - Error messages, messages containing "error" or "!!"

!! Error: Unknown command
!! Emergency stop
Error: Connection lost

Visual Feedback

Syntax highlighting provides immediate visual feedback:

1. Command Recognition: Green/cyan highlighting confirms the command is recognized
2. Typo Detection: White highlighting suggests a potential typo
3. Status Understanding: Color-coded responses help you quickly understand printer state

Examples

Successful Command Flow

> G28                           # Green (recognized)
// Homing X Y Z                 # Cyan (info)
ok                              # Green (success)

> M104 S200                     # Green (recognized)
// Setting extruder to 200.0    # Cyan (info)
ok                              # Green (success)

Error Handling

> INVALID_COMMAND               # White (not recognized)
!! Unknown command              # Red (error)

> M999                          # Green (recognized but causes error)
!! Error: Invalid command      # Red (error)

Macro Execution

> PRINT_START                   # Cyan (macro)
// Executing PRINT_START        # Cyan (info)
// Homing all axes              # Cyan (info)
// Heating bed to 60            # Cyan (info)
ok                              # Green (success)

Benefits

Quick Recognition

• Spot typos instantly before pressing Enter
• Distinguish macros from G-code at a glance
• Understand command type immediately

Error Prevention

• White highlighting warns you before executing unknown commands
• Helps catch case-sensitive macro names
• Visual confirmation of command recognition

Faster Workflow

• No need to wait for error messages
• Quick visual scanning of command history
• Immediate feedback reduces mistakes

Technical Details

Highlighting is applied in real-time using the colored crate:

• Processed character-by-character as you type
• Zero latency on modern systems
• Works in all terminal emulators with color support

Terminal Compatibility

Syntax highlighting works in:

• ✅ Terminal.app (macOS)
• ✅ iTerm2 (macOS)
• ✅ GNOME Terminal (Linux)
• ✅ Konsole (Linux)
• ✅ Windows Terminal
• ✅ xterm
• ✅ Most modern terminal emulators

Customization

Future Feature

Custom color schemes are planned for a future release.

Next Steps

• Tab Completion - Command autocompletion
• Command History - Navigate previous commands
• Interactive Mode - Full REPL features