Go for Python Programmers

Go for Python Programmers presented at DevConf.CZ 2019

Transcript

1. Go for Python Programmers
   Alexandre Vicenzi
   Pythonista at Red Hat
   

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2. History
   ● Robert Griesemer, Rob Pike and Ken Thompson
   ● Google
   ● Began in late 2007
   ● First public release in 2009
   ● First stable release in 2012
   

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3. Why a new language?
   ● Frustration with existing languages
   ● Programming had become too difficult
   ● Many years with a quiet landscape of choices
   ● To take advantage of networking and multicore
   

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4. Features
   ● Compiles to native machine code
   ● Memory safety
   ● Garbage collection
   ● Concurrency
   

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5. Go vs Python
   

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6. Code organization
   ● Keep everything in a single workspace
   ○ src - source files
   ○ bin - executable commands
   ● GOPATH environment variable ($HOME/go)
   ● Workspace contains multiple repositories
   ● Import path is the package location in the workspace
   

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7. Package management
   ● No official tool yet
   ● Tools
   ○ dep - The official experiment
   ○ Godep
   ○ Govendor
   ○ Glide
   ○ many others
   ● Modules
   ○ Preliminary support
   ○ No need for GOPATH anymore
   ○ Go 1.13 (August 2019)
   

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8. Object Oriented Programming
   ● No classes
   ● No inheritance
   ● No generics
   ● Interfaces
   ● Composition
   ● Type embedding
   

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9. Pointers
   ● Everything in Go is passed by value
   ● No pointer arithmetic
   ● Pointer is represented by *
   ● * is also used to “dereference”
   ● & returns the memory address
   ● new function
   

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10. Go concurrency
    ● Goroutines
    ○ Function executing concurrently with other functions in the same address space
    ○ Goroutines are multiplexed onto multiple OS threads
    ● Channels
    ○ Typed, synchronized, thread-safe by design
    ○ Buffered and Unbuffered (default)
    

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11. What else is different?
    ● No decorators
    ● No named or optional arguments
    ● No iterators
    ● No generators
    ● No exceptions
    ● Part of the C family
    ● Labels and goto
    

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12. Your first program
    package main
    import "fmt"
    func main() {
    fmt.Println("Hello, world.")
    }
    

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13. factorial.py
    def factorial(n):
    if n == 0:
    return 1
    return n * factorial(n - 1)
    print(factorial(5))
    

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14. factorial.go
    package main
    import "fmt"
    func factorial(n int) int {
    if n == 0 {
    return 1
    }
    return n * factorial(n-1)
    }
    func main() {
    fmt.Println(factorial(5))
    }
    

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15. fibonacci.py
    def fibonacci(n):
    a, b = 0, 1
    yield a
    for i in range(n):
    a, b = b, a + b
    yield a
    for i in fibonacci(10):
    print(i)
    

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16. fibonacci.go
    package main
    import "fmt"
    func fibonacci(c chan int, n int) {
    a, b := 0, 1
    c <- a
    for i := 0; i < n; i++ {
    a, b = b, a+b
    c <- a
    }
    close(c)
    }
    func main() {
    c := make(chan int)
    go fibonacci(c, 10)
    for i := range c {
    fmt.Println(i)
    }
    }
    

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18. Conclusion
    Go is
    ● Simple
    ● Concurrent
    ● Robust
    ● Fun
    

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19. Next steps
    ● golang.org
    ● tour.golang.org
    ● groups.google.com/d/forum/golang-nuts
    ● golang-book.com
    

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20. Thank you
    Alexandre Vicenzi
    Pythonista at Red Hat
    alexandrevicenzi.com
    @alxvicenzi
    

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