| 执行方式 |
1 交互模式:
＄ pyhthon
>>> print “Hello, World!”
2 文件模式
＄ echo ‘print “Hello, World!”’ > test.py
＄ python test.py
Hello, World!
3 命令模式：
修改文件 test.py:
#!/usr/bin/python
print “Hello, Python!”
修改变成可执行文件
＄ chmod +x test.py
＄./test.py |
package main
import “fmt”
func main() {
fmt.Println(“Hello, World!”:
}
＄ go run |
| 标识符 |
大写：类名
_A: 私有
＿＿A：强私有
＿A＿:语言特殊定义 |
大写：公共标识符
其他：私有标识符 |
| 判断 |
if True:
print “True”
else:
print “False”
if (i == 100): print “i = 100”
其他：
elif |
if true {
fmt.Println(“True”)
} else {
fmt.Println(“False”)
}其他：
else if |
| 循环 |
fruits = [“apple”, “banana”, “cherry”]
for x in fruits:
print(x)
或者：
for x in range(0, len(fruits), 1):
print(x)
或者：
i = 1
while i < 3:
print(i)
i += 1
其他：
break, continue |
fruits := []string{“apple”, “banana”, “cherry”}
for _, x := range fruits {
fmt.Println(x)
}
或者：
for i:= 0; i < len(fruits); i++ {
fmt.Println(fruits[i]);
}
其他：
break, continue |
| 注释 |
# This is a comment.
print(“Hello, World!”) |
// This is a comment.
fmt.Println(“Hello, World!”)
/* This comment
can cross multiple lines. */ |
| 字符串 |
‘hello’
“hello”
”“” Hello,
World!“”” |
‘c’ // character
“string”
` Hello,
World!` |
| list |
thislist = [“apple”, “banana”, “cherry”]
print(thislist)
print(thislist[1])
thislist.append(“orange”)
thislist.insert(1, “orange”)
thislist.remove(“banana”)
thislist.pop()
del thislist[0]
thislist.clear()
print(len(thislist))
del thislist |
thislist := string{“apple”, “banana”, “cherry”}
fmt.Println(thislist)
fmt.Println(thislist[1])
thislist = thislist.append(“orange”)
// no simple operation for insert
// and remove
// and pop
// and delete
// and clear
fmt.Println(len(thislist))
thislist = nil |
| tuple |
A tuple is a collection which is ordered and unchangeable
thistuple = (“apple”, “banana”, “cherry”)
print(thistuple)
print(thistuple[1])
thistuple[1] = “blackcurrant”
if “apple” in thistuple:
print(“Yes, ‘apple’ is in the fruits tuple”) |
There is no tuple in go, but how about https://github.com/kmanley/golang-tuple |
| set |
thisset = {“apple”, “banana”, “cherry”}
print(thisset)
print(“banana” in thisset)
thisset.add(“orange”)
thisset.remove(“banana”) |
m := map[string]bool
for _, x := range m {
fmt.Println(x)
}
x, ok := m[“banana”]
fmt.Println(ok)
m[“orange”]=true
delete(m, “banana”) |
| dict |
thisdict = {
“brand”: “Ford”,
“model”: “Mustang”,
“year”: 1964
}
print(thisdict) |
thisdict := map[string]string{
“brand”: “Ford”,
“model”: “Mustang”,
“year”: 1964,
}
fmt.Println(thisdict) |
| fucntions |
def my_function(x):
return 5 * x
my_function(3) |
func my_function(x float64) float64 {
return 5 * x
}
my_function(3) |
| lambda |
x = lambda a : a + 10
print(x(5)) |
x := func(a int) int { return a + 10}
fmt.Println(x(5)) |
| class |
MyClass:
x = 5
p1 = MyClass()
print(p1.x |
type MyClass struct {
x int
}
p1 := MyClass{5}
fmt.Println(p1.x) |
| _init_ |
class Person:
def init(self, name, age):
self.name = name
self.age = age
def myfunc(self):
print(“Hello my name is ” + self.name)
p1 = Person(“John”, 36)
print(p1.name)
print(p1.age) |
type Person struct {
name string
age int
}
func NewPerson(name string, age int) *Person {
p := &Person{name, age}
return p
}
func (self *Person) myfunc() {
fmt.Println(“Hello my name is ” + self.name)
}p1 := NewPerson(“John”, 36)
fmt.Println(p1.name, p1.age) |
| import |
import mymodule as mx |
import mx “mymodule” |
| try…catch |
try:
f = open(“demofile.txt”)
f.write(“Lorum Ipsum”)
except:
print(“Something went wrong when writing to the file”)
finally:
f.close() |
func main() {
defer func(){
if err:=recover();err!=nil{
fmt.Println(err)
}
}()
file, err := os.Open(“demofile.txt”)
if err != nil {
panic(errors.New(“Someting went wrong when writing to the file”))
}
file.WriteString(“Lorum Ipsum”)
} |
