Polymorphism in Go

Polymorphism in object-oriented programming refers to the ability of an object to take on many forms. In Go, polymorphism is achieved through interfaces:

type SoundMaker interface {
    MakeSound()
}

func ProduceSound(s SoundMaker) {
    s.MakeSound()
}

Go vs Java Comparison

Language Fundamentals

Object Orientation

Concurrency Models

Basic Data Types in Go

Primitive Types

• Boolean: bool
• Numeric:
  • Integers: int8-int64, uint8-uint64
  • Floating-point: float32, float64
  • Complex: complex64, complex128
• Text: string

Composite Types

• Arrrays
• Slices
• Maps
• Structs
• Pointers
• Functions
• Interfaces
• Channels

String Traversal Methods

Byte-by-Byte

s := "Hello"
for i := 0; i < len(s); i++ {
    fmt.Printf("%c ", s[i])
}

Rune-by-Rune

s := "世界"
for _, r := range s {
    fmt.Printf("%c ", r)
}

Byte vs Rune

GMP Scheduling Model

• G: Goroutine (task unit)
• M: OS thread (execution context)
• P: Logical processor (scheduler)

Workflow:

1. Goroutines are created and queued
2. P assigns G to M for execution
3. On blocking, M may be released

Parameter Passing

Go always uses value passing, though some types contain references:

String Immutability

Go strings are immutable for:

• Safety
• Performance
• Memory management

To modify:

s := "hello"
b := []byte(s)
b[0] = 'H'
s = string(b)

Generics Implementation

Go's generics are implemented through:

• Type parameters
• Compile-time monomorphization
• Runtime type erasure