what.md

What I Learned Today 🎓

1. Zed Tasks System 📋

File Requirements

• Tasks must be named .zed/tasks.json (NOT .jsonc)
• Zed's JSON parser accepts JSONC syntax (comments with //)
• No trailing commas allowed - this was the key issue!

Task Structure

[
  {
    "label": "Task Name",
    "command": "command to run",
    "cwd": "${ZED_WORKTREE_ROOT}",
    "tags": ["category"]
  }
]

Using Tasks

• Open with cmd-shift-p → task: spawn (or opt-shift-t)
• Rerun last task: task: rerun (or opt-t)
• Tasks are filtered by available variables

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2. Unix Philosophy & Standard Streams 🔀

The Power of stdout

Instead of complicated HTTP servers and curl commands, the Unix way is simpler:

go run main.go > output.gif

How It Works

func main() {
    lissajous(os.Stdout)  // Write to standard output
}

• os.Stdout = standard output stream
• Shell's > operator redirects it to a file
• Without >, binary data appears as garbage in terminal

Why This is Better

✅ Flexible: Users decide where output goes

./program > file.gif           # Save to file
./program | display -          # Pipe to image viewer
./program > /dev/null          # Discard output

✅ Simple: No need for file handling in code ✅ Composable: Works with other Unix tools

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3. Go Binary Compilation 🔨

What go build Does

1. Compiles Go source code to machine code
2. Links all dependencies
3. Creates a standalone executable
4. No Go runtime needed to run it

Example

go build -o bin/lissajous main.go

Result:

• Input: main.go (~4KB source code)
• Output: bin/lissajous (~2.4MB executable)
• Format: Mach-O 64-bit executable arm64 (for Apple Silicon)

Benefits

• ⚡ Fast startup - no compilation at runtime
• 📦 Portable - copy to another machine and it works
• 🚀 No dependencies - users don't need Go installed
• 💨 Native performance - runs at full CPU speed

Running the Binary

# Instead of:
go run main.go > output.gif

# You can:
./bin/lissajous > output.gif

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4. Cross-Compilation 🌍

Go can build binaries for different platforms from a single machine:

# For Linux
GOOS=linux GOARCH=amd64 go build -o bin/lissajous-linux main.go

# For Windows
GOOS=windows GOARCH=amd64 go build -o bin/lissajous.exe main.go

# For macOS Intel
GOOS=darwin GOARCH=amd64 go build -o bin/lissajous-mac-intel main.go

# For macOS ARM (M1/M2/M3)
GOOS=darwin GOARCH=arm64 go build -o bin/lissajous-mac-arm main.go

This means you can distribute your program to users on any platform! 🎉

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5. Code Organization Best Practices 📁

Commenting vs Deleting

Instead of deleting old code, comment it out with explanations:

// Uncomment below to run as HTTP server:
// handler := func(w http.ResponseWriter, r *http.Request){
//     lissajous(w)
// }
// http.HandleFunc("/", handler)
// log.Fatal(http.ListenAndServe("localhost:8000", nil))

// Output GIF to stdout (use with: go run main.go > output.gif)
lissajous(os.Stdout)

Why?

• Easy to switch between modes
• Preserves working code
• Documents alternative approaches
• Helps future you remember options

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Key Takeaways 💡

1. Keep it simple - go run main.go > output.gif beats complex HTTP + curl
2. Write to stdout - Let the shell handle redirection
3. Binaries are powerful - Distribute standalone executables
4. Comment, don't delete - Preserve alternative implementations
5. Unix philosophy - Do one thing well, compose with others

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Project Structure

go_pp/
├── .zed/
│   └── tasks.json          # Zed task definitions
├── shape/
│   └── main.go             # Shape animations server
├── main.go                 # Lissajous GIF generator
├── go.mod                  # Go module file
└── *.gif                   # Generated animations

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Useful Commands

# Generate GIF
go run main.go > output.gif

# Build binary
go build -o bin/lissajous main.go

# Run binary
./bin/lissajous > output.gif

# Format and vet code
go fmt ./... && go vet ./...

# Open GIF (macOS)
open output.gif

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Last updated: 2024