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Update to Julia 1.0 (Finish 6/6)
This commit is contained in:
0u0
@@ -336,7 +336,6 @@ intersect(filled_set, other_set) # => Set([4, 3, 5])
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union(filled_set, other_set) # => Set([4, 2, 3, 5, 6, 1])
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union(filled_set, other_set) # => Set([4, 2, 3, 5, 6, 1])
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setdiff(Set([1,2,3,4]), Set([2,3,5])) # => Set([4, 1])
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setdiff(Set([1,2,3,4]), Set([2,3,5])) # => Set([4, 1])
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####################################################
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####################################################
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## 3. 控制语句
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## 3. 控制语句
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####################################################
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####################################################
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@@ -409,81 +408,88 @@ catch e
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end
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end
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# => caught it ErrorException("help")
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# => caught it ErrorException("help")
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####################################################
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####################################################
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## 4. 函数
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## 4. 函数
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####################################################
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####################################################
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# 用关键字 'function' 可创建一个新函数
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# 关键字 'function' 用于定义函数
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#function name(arglist)
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# function name(arglist)
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# body...
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# body...
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#end
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# end
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function add(x, y)
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function add(x, y)
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println("x is $x and y is $y")
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println("x is $x and y is $y")
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# 最后一行语句的值为返回
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# 函数会返回最后一行的值
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x + y
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x + y
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end
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end
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add(5, 6) # => 在 "x is 5 and y is 6" 后会打印 11
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add(5, 6)
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# => x is 5 and y is 6
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# => 11
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# 更紧凑的定义函数
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f_add(x, y) = x + y # => f_add (generic function with 1 method)
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f_add(3, 4) # => 7
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# 函数可以将多个值作为元组返回
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fn(x, y) = x + y, x - y # => fn (generic function with 1 method)
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fn(3, 4) # => (7, -1)
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# 还可以定义接收可变长参数的函数
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# 还可以定义接收可变长参数的函数
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function varargs(args...)
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function varargs(args...)
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return args
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return args
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# 关键字 return 可在函数内部任何地方返回
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# 使用 return 可以在函数内的任何地方返回
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end
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end
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# => varargs (generic function with 1 method)
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# => varargs (generic function with 1 method)
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varargs(1,2,3) # => (1,2,3)
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varargs(1,2,3) # => (1,2,3)
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# 省略号 ... 被称为 splat.
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# 省略号 ... 称为 splat
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# 刚刚用在了函数定义中
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# 刚刚用在了函数定义中
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# 还可以用在函数的调用
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# 在调用函数时也可以使用它，此时它会把数组或元组解包为参数列表
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# Array 或者 Tuple 的内容会变成参数列表
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add([5,6]...) # 等价于 add(5,6)
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Set([1,2,3]) # => Set{Array{Int64,1}}([1,2,3]) # 获得一个 Array 的 Set
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Set([1,2,3]...) # => Set{Int64}(1,2,3) # 相当于 Set(1,2,3)
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x = (1,2,3) # => (1,2,3)
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x = (5, 6) # => (5,6)
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Set(x) # => Set{(Int64,Int64,Int64)}((1,2,3)) # 一个 Tuple 的 Set
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add(x...) # 等价于 add(5,6)
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Set(x...) # => Set{Int64}(2,3,1)
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# 可定义带可选参数的函数
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# 可定义可选参数的函数
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function defaults(a, b, x=5, y=6)
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function defaults(a,b,x=5,y=6)
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return "$a $b and $x $y"
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return "$a $b and $x $y"
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end
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end
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# => defaults (generic function with 3 methods)
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defaults('h','g') # => "h g and 5 6"
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defaults('h', 'g') # => "h g and 5 6"
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defaults('h','g','j') # => "h g and j 6"
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defaults('h', 'g', 'j') # => "h g and j 6"
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defaults('h','g','j','k') # => "h g and j k"
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defaults('h', 'g', 'j', 'k') # => "h g and j k"
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try
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try
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defaults('h') # => ERROR: no method defaults(Char,)
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defaults('h') # => ERROR: MethodError: no method matching defaults(::Char)
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defaults() # => ERROR: no methods defaults()
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defaults() # => ERROR: MethodError: no method matching defaults()
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catch e
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catch e
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println(e)
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println(e)
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end
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end
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# 还可以定义键值对的参数
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# 还可以定义带关键字参数的函数
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function keyword_args(;k1=4,name2="hello") # note the ;
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function keyword_args(;k1=4, name2="hello") # 注意分号 ';'
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return ["k1"=>k1,"name2"=>name2]
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return Dict("k1" => k1, "name2" => name2)
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end
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end
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# => keyword_args (generic function with 1 method)
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keyword_args(name2="ness") # => ["name2"=>"ness","k1"=>4]
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keyword_args(name2="ness") # => ["name2"=>"ness", "k1"=>4]
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keyword_args(k1="mine") # => ["k1"=>"mine","name2"=>"hello"]
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keyword_args(k1="mine") # => ["name2"=>"hello", "k1"=>"mine"]
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keyword_args() # => ["name2"=>"hello","k1"=>4]
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keyword_args() # => ["name2"=>"hello", "k1"=>4]
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# 可以组合各种类型的参数在同一个函数的参数列表中
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# 可以在一个函数中组合各种类型的参数
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function all_the_args(normal_arg, optional_positional_arg=2; keyword_arg="foo")
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function all_the_args(normal_arg, optional_positional_arg=2; keyword_arg="foo")
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println("normal arg: $normal_arg")
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println("normal arg: $normal_arg")
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println("optional arg: $optional_positional_arg")
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println("optional arg: $optional_positional_arg")
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println("keyword arg: $keyword_arg")
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println("keyword arg: $keyword_arg")
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end
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end
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# => all_the_args (generic function with 2 methods)
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all_the_args(1, 3, keyword_arg=4)
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all_the_args(1, 3, keyword_arg=4)
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# prints:
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# => normal arg: 1
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# normal arg: 1
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# => optional arg: 3
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# optional arg: 3
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# => keyword arg: 4
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# keyword arg: 4
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# Julia 有一等函数
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# Julia 有一等函数
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function create_adder(x)
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function create_adder(x)
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@@ -492,14 +498,16 @@ function create_adder(x)
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end
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end
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return adder
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return adder
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end
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end
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# => create_adder (generic function with 1 method)
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# 这是用 "stabby lambda syntax" 创建的匿名函数
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# 这是用 "stabby lambda syntax" 创建的匿名函数
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(x -> x > 2)(3) # => true
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(x -> x > 2)(3) # => true
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# 这个函数和上面的 create_adder 一模一样
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# 这个函数和上面的 create_adder 是等价的
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function create_adder(x)
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function create_adder(x)
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y -> x + y
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y -> x + y
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end
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end
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# => create_adder (generic function with 1 method)
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# 你也可以给内部函数起个名字
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# 你也可以给内部函数起个名字
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function create_adder(x)
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function create_adder(x)
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@@ -508,17 +516,18 @@ function create_adder(x)
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end
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end
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adder
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adder
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end
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end
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# => create_adder (generic function with 1 method)
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add_10 = create_adder(10)
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add_10 = create_adder(10) # => (::getfield(Main, Symbol("#adder#11")){Int64})
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# (generic function with 1 method)
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add_10(3) # => 13
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add_10(3) # => 13
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# 内置的高阶函数有
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# 内置的高阶函数有
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map(add_10, [1,2,3]) # => [11, 12, 13]
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map(add_10, [1,2,3]) # => [11, 12, 13]
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filter(x -> x > 5, [3, 4, 5, 6, 7]) # => [6, 7]
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filter(x -> x > 5, [3, 4, 5, 6, 7]) # => [6, 7]
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# 还可以使用 list comprehensions 替代 map
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# 还可以使用 list comprehensions 让 map 更美观
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[add_10(i) for i=[1, 2, 3]] # => [11, 12, 13]
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[add_10(i) for i = [1, 2, 3]] # => [11, 12, 13]
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[add_10(i) for i in [1, 2, 3]] # => [11, 12, 13]
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[add_10(i) for i in [1, 2, 3]] # => [11, 12, 13]
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####################################################
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####################################################
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@@ -535,90 +544,97 @@ typeof(Int64) # => DataType
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typeof(DataType) # => DataType
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typeof(DataType) # => DataType
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# DataType 是代表类型的类型，也代表他自己的类型
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# DataType 是代表类型的类型，也代表他自己的类型
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# 类型可用作文档化，优化，以及调度
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# 类型可用于文档化代码、执行优化以及多重派分(dispatch)
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# 并不是静态检查类型
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# Julia 并不只是静态的检查类型
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# 用户还可以自定义类型
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# 用户还可以自定义类型
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# 跟其他语言的 records 或 structs 一样
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# 就跟其它语言的 records 或 structs 一样
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# 用 `type` 关键字定义新的类型
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# 用 `struct` 关键字定义新的类型
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# type Name
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# struct Name
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# field::OptionalType
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# field::OptionalType
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# ...
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# ...
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# end
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# end
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type Tiger
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struct Tiger
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taillength::Float64
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taillength::Float64
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coatcolor # 不附带类型标注的相当于 `::Any`
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coatcolor # 不带类型标注相当于 `::Any`
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end
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end
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# 构造函数参数是类型的属性
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# 默认构造函数的参数是类型的属性，按类型定义中的顺序排列
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tigger = Tiger(3.5,"orange") # => Tiger(3.5,"orange")
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tigger = Tiger(3.5, "orange") # => Tiger(3.5, "orange")
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# 用新类型作为构造函数还会创建一个类型
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# 用新类型作为构造函数还会创建一个类型
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sherekhan = typeof(tigger)(5.6,"fire") # => Tiger(5.6,"fire")
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sherekhan = typeof(tigger)(5.6, "fire") # => Tiger(5.6, "fire")
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# struct 类似的类型被称为具体类型
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# 类似 struct 的类型被称为具体类型
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# 他们可被实例化但不能有子类型
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# 它们可被实例化，但不能有子类型
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# 另一种类型是抽象类型
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# 另一种类型是抽象类型
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# abstract Name
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# 抽象类型名
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abstract Cat # just a name and point in the type hierarchy
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abstract type Cat end # 仅仅是指向类型结构层次的一个名称
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|
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# 抽象类型不能被实例化，但是可以有子类型
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# 抽象类型不能被实例化，但可以有子类型
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# 例如，Number 就是抽象类型
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# 例如，Number 就是抽象类型
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subtypes(Number) # => 6-element Array{Any,1}:
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subtypes(Number) # => 2-element Array{Any,1}:
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# Complex{Float16}
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# => Complex
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# Complex{Float32}
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# => Real
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# Complex{Float64}
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# Complex{T<:Real}
|
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# ImaginaryUnit
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# Real
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subtypes(Cat) # => 0-element Array{Any,1}
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subtypes(Cat) # => 0-element Array{Any,1}
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# 所有的类型都有父类型; 可以用函数 `super` 得到父类型.
|
# AbstractString，类如其名，也是一个抽象类型
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typeof(5) # => Int64
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subtypes(AbstractString) # => 4-element Array{Any,1}:
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super(Int64) # => Signed
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# => String
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super(Signed) # => Real
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# => SubString
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super(Real) # => Number
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# => SubstitutionString
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super(Number) # => Any
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# => Test.GenericString
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super(super(Signed)) # => Number
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super(Any) # => Any
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# 所有这些类型，除了 Int64, 都是抽象类型.
|
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|
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# <: 是类型集成操作符
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# 所有的类型都有父类型。可以用函数 `supertype` 得到父类型
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type Lion <: Cat # Lion 是 Cat 的子类型
|
typeof(5) # => Int64
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||||||
|
supertype(Int64) # => Signed
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||||||
|
supertype(Signed) # => Integer
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||||||
|
supertype(Integer) # => Real
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||||||
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supertype(Real) # => Number
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||||||
|
supertype(Number) # => Any
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||||||
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supertype(supertype(Signed)) # => Real
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||||||
|
supertype(Any) # => Any
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|
# 除了 Int64 外，其余的类型都是抽象类型
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||||||
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typeof("fire") # => String
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||||||
|
supertype(String) # => AbstractString
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||||||
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supertype(AbstractString) # => Any
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||||||
|
supertype(SubString) # => AbstractString
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||||||
|
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|
# <: 是子类型化操作符
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|
struct Lion <: Cat # Lion 是 Cat 的子类型
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mane_color
|
mane_color
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roar::String
|
roar::AbstractString
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||||||
end
|
end
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||||||
|
|
||||||
# 可以继续为你的类型定义构造函数
|
# 可以继续为你的类型定义构造函数
|
||||||
# 只需要定义一个同名的函数
|
# 只需要定义一个与类型同名的函数，并调用已有的构造函数得到正确的类型
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||||||
# 并调用已有的构造函数设置一个固定参数
|
Lion(roar::AbstractString) = Lion("green", roar) # => Lion
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Lion(roar::String) = Lion("green",roar)
|
# 这是一个外部构造函数，因为它在类型定义之外
|
||||||
# 这是一个外部构造函数，因为他再类型定义之外
|
|
||||||
|
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||||||
type Panther <: Cat # Panther 也是 Cat 的子类型
|
struct Panther <: Cat # Panther 也是 Cat 的子类型
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||||||
eye_color
|
eye_color
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||||||
Panther() = new("green")
|
Panther() = new("green")
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||||||
# Panthers 只有这个构造函数，没有默认构造函数
|
# Panthers 只有这个构造函数，没有默认构造函数
|
||||||
end
|
end
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||||||
# 使用内置构造函数，如 Panther，可以让你控制
|
# 像 Panther 一样使用内置构造函数，让你可以控制如何构建类型的值
|
||||||
# 如何构造类型的值
|
# 应该尽量使用外部构造函数，而不是内部构造函数
|
||||||
# 应该尽可能使用外部构造函数而不是内部构造函数
|
|
||||||
|
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||||||
####################################################
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####################################################
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||||||
## 6. 多分派
|
## 6. 多分派
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||||||
####################################################
|
####################################################
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||||||
|
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||||||
# 在Julia中, 所有的具名函数都是类属函数
|
# Julia 中所有的函数都是通用函数，或者叫做泛型函数(generic functions)
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||||||
# 这意味着他们都是有很大小方法组成的
|
# 也就是说这些函数都是由许多小方法组合而成的
|
||||||
# 每个 Lion 的构造函数都是类属函数 Lion 的方法
|
# Lion 的每一种构造函数都是通用函数 Lion 的一个方法
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||||||
|
|
||||||
# 我们来看一个非构造函数的例子
|
# 我们来看一个非构造函数的例子
|
||||||
|
# 首先，让我们定义一个函数 meow
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||||||
|
|
||||||
# Lion, Panther, Tiger 的 meow 定义为
|
# Lion, Panther, Tiger 的 meow 定义分别为
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||||||
function meow(animal::Lion)
|
function meow(animal::Lion)
|
||||||
animal.roar # 使用点符号访问属性
|
animal.roar # 使用点记号 '.' 访问属性
|
||||||
end
|
end
|
||||||
|
|
||||||
function meow(animal::Panther)
|
function meow(animal::Panther)
|
||||||
@@ -630,149 +646,198 @@ function meow(animal::Tiger)
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|||||||
end
|
end
|
||||||
|
|
||||||
# 试试 meow 函数
|
# 试试 meow 函数
|
||||||
meow(tigger) # => "rawwr"
|
meow(tigger) # => "rawwwr"
|
||||||
meow(Lion("brown","ROAAR")) # => "ROAAR"
|
meow(Lion("brown", "ROAAR")) # => "ROAAR"
|
||||||
meow(Panther()) # => "grrr"
|
meow(Panther()) # => "grrr"
|
||||||
|
|
||||||
# 再看看层次结构
|
# 回顾类型的层次结构
|
||||||
issubtype(Tiger,Cat) # => false
|
Tiger <: Cat # => false
|
||||||
issubtype(Lion,Cat) # => true
|
Lion <: Cat # => true
|
||||||
issubtype(Panther,Cat) # => true
|
Panther <: Cat # => true
|
||||||
|
|
||||||
# 定义一个接收 Cats 的函数
|
# 定义一个接收 Cat 类型的函数
|
||||||
function pet_cat(cat::Cat)
|
function pet_cat(cat::Cat)
|
||||||
println("The cat says $(meow(cat))")
|
println("The cat says $(meow(cat))")
|
||||||
end
|
end
|
||||||
|
# => pet_cat (generic function with 1 method)
|
||||||
|
|
||||||
pet_cat(Lion("42")) # => prints "The cat says 42"
|
pet_cat(Lion("42")) # => The cat says 42
|
||||||
try
|
try
|
||||||
pet_cat(tigger) # => ERROR: no method pet_cat(Tiger,)
|
pet_cat(tigger) # => ERROR: MethodError: no method matching pet_cat(::Tiger)
|
||||||
catch e
|
catch e
|
||||||
println(e)
|
println(e)
|
||||||
end
|
end
|
||||||
|
|
||||||
# 在面向对象语言中，通常都是单分派
|
# 在面向对象语言中，通常都是单分派
|
||||||
# 这意味着分派方法是通过第一个参数的类型决定的
|
# 这意味着使用的方法取决于第一个参数的类型
|
||||||
# 在Julia中, 所有参数类型都会被考虑到
|
# 而 Julia 中选择方法时会考虑到所有参数的类型
|
||||||
|
|
||||||
# 让我们定义有多个参数的函数，好看看区别
|
# 让我们定义一个有更多参数的函数，这样我们就能看出区别
|
||||||
function fight(t::Tiger,c::Cat)
|
function fight(t::Tiger, c::Cat)
|
||||||
println("The $(t.coatcolor) tiger wins!")
|
println("The $(t.coatcolor) tiger wins!")
|
||||||
end
|
end
|
||||||
# => fight (generic function with 1 method)
|
# => fight (generic function with 1 method)
|
||||||
|
|
||||||
fight(tigger,Panther()) # => prints The orange tiger wins!
|
fight(tigger, Panther()) # => The orange tiger wins!
|
||||||
fight(tigger,Lion("ROAR")) # => prints The orange tiger wins!
|
fight(tigger, Lion("ROAR")) # => fight(tigger, Lion("ROAR"))
|
||||||
|
|
||||||
# 让我们修改一下传入具体为 Lion 类型时的行为
|
# 让我们修改一下传入 Lion 类型时的行为
|
||||||
fight(t::Tiger,l::Lion) = println("The $(l.mane_color)-maned lion wins!")
|
fight(t::Tiger, l::Lion) = println("The $(l.mane_color)-maned lion wins!")
|
||||||
# => fight (generic function with 2 methods)
|
# => fight (generic function with 2 methods)
|
||||||
|
|
||||||
fight(tigger,Panther()) # => prints The orange tiger wins!
|
fight(tigger, Panther()) # => The orange tiger wins!
|
||||||
fight(tigger,Lion("ROAR")) # => prints The green-maned lion wins!
|
fight(tigger, Lion("ROAR")) # => The green-maned lion wins!
|
||||||
|
|
||||||
# 把 Tiger 去掉
|
# 我们不需要一只老虎参与战斗
|
||||||
fight(l::Lion,c::Cat) = println("The victorious cat says $(meow(c))")
|
fight(l::Lion, c::Cat) = println("The victorious cat says $(meow(c))")
|
||||||
# => fight (generic function with 3 methods)
|
# => fight (generic function with 3 methods)
|
||||||
|
|
||||||
fight(Lion("balooga!"),Panther()) # => prints The victorious cat says grrr
|
fight(Lion("balooga!"), Panther()) # => The victorious cat says grrr
|
||||||
try
|
try
|
||||||
fight(Panther(),Lion("RAWR")) # => ERROR: no method fight(Panther,Lion)
|
fight(Panther(), Lion("RAWR"))
|
||||||
catch
|
# => ERROR: MethodError: no method matching fight(::Panther, ::Lion)
|
||||||
|
# => Closest candidates are:
|
||||||
|
# => fight(::Tiger, ::Lion) at ...
|
||||||
|
# => fight(::Tiger, ::Cat) at ...
|
||||||
|
# => fight(::Lion, ::Cat) at ...
|
||||||
|
# => ...
|
||||||
|
catch e
|
||||||
|
println(e)
|
||||||
end
|
end
|
||||||
|
|
||||||
# 在试试让 Cat 在前面
|
# 试试把 Cat 放在前面
|
||||||
fight(c::Cat,l::Lion) = println("The cat beats the Lion")
|
fight(c::Cat, l::Lion) = println("The cat beats the Lion")
|
||||||
# => Warning: New definition
|
# => fight (generic function with 4 methods)
|
||||||
# fight(Cat,Lion) at none:1
|
|
||||||
# is ambiguous with
|
|
||||||
# fight(Lion,Cat) at none:2.
|
|
||||||
# Make sure
|
|
||||||
# fight(Lion,Lion)
|
|
||||||
# is defined first.
|
|
||||||
#fight (generic function with 4 methods)
|
|
||||||
|
|
||||||
# 警告说明了无法判断使用哪个 fight 方法
|
# 由于无法判断该使用哪个 fight 方法，而产生了错误
|
||||||
fight(Lion("RAR"),Lion("brown","rarrr")) # => prints The victorious cat says rarrr
|
try
|
||||||
# 结果在老版本 Julia 中可能会不一样
|
fight(Lion("RAR"), Lion("brown", "rarrr"))
|
||||||
|
# => ERROR: MethodError: fight(::Lion, ::Lion) is ambiguous. Candidates:
|
||||||
|
# => fight(c::Cat, l::Lion) in Main at ...
|
||||||
|
# => fight(l::Lion, c::Cat) in Main at ...
|
||||||
|
# => Possible fix, define
|
||||||
|
# => fight(::Lion, ::Lion)
|
||||||
|
# => ...
|
||||||
|
catch e
|
||||||
|
println(e)
|
||||||
|
end
|
||||||
|
# 在不同版本的 Julia 中错误信息可能有所不同
|
||||||
|
|
||||||
fight(l::Lion,l2::Lion) = println("The lions come to a tie")
|
fight(l::Lion, l2::Lion) = println("The lions come to a tie")
|
||||||
fight(Lion("RAR"),Lion("brown","rarrr")) # => prints The lions come to a tie
|
# => fight (generic function with 5 methods)
|
||||||
|
fight(Lion("RAR"), Lion("brown", "rarrr")) # => The lions come to a tie
|
||||||
|
|
||||||
|
|
||||||
# Under the hood
|
# Under the hood
|
||||||
# 你还可以看看 llvm 以及生成的汇编代码
|
# 你还可以看看 llvm 以及它生成的汇编代码
|
||||||
|
|
||||||
square_area(l) = l * l # square_area (generic function with 1 method)
|
square_area(l) = l * l # => square_area (generic function with 1 method)
|
||||||
|
square_area(5) # => 25
|
||||||
|
|
||||||
square_area(5) #25
|
# 当我们喂给 square_area 一个整数时会发生什么？
|
||||||
|
|
||||||
# 给 square_area 一个整形时发生什么
|
|
||||||
code_native(square_area, (Int32,))
|
code_native(square_area, (Int32,))
|
||||||
# .section __TEXT,__text,regular,pure_instructions
|
# .text
|
||||||
# Filename: none
|
# ; Function square_area {
|
||||||
# Source line: 1 # Prologue
|
# ; Location: REPL[49]:1
|
||||||
# push RBP
|
# pushq %rbp
|
||||||
# mov RBP, RSP
|
# movq %rsp, %rbp
|
||||||
# Source line: 1
|
# ; Function *; {
|
||||||
# movsxd RAX, EDI # Fetch l from memory?
|
# ; Location: int.jl:54
|
||||||
# imul RAX, RAX # Square l and store the result in RAX
|
# imull %ecx, %ecx
|
||||||
# pop RBP # Restore old base pointer
|
# ;}
|
||||||
# ret # Result will still be in RAX
|
# movl %ecx, %eax
|
||||||
|
# popq %rbp
|
||||||
|
# retq
|
||||||
|
# nopl (%rax,%rax)
|
||||||
|
# ;}
|
||||||
|
|
||||||
code_native(square_area, (Float32,))
|
code_native(square_area, (Float32,))
|
||||||
# .section __TEXT,__text,regular,pure_instructions
|
# .text
|
||||||
# Filename: none
|
# ; Function square_area {
|
||||||
# Source line: 1
|
# ; Location: REPL[49]:1
|
||||||
# push RBP
|
# pushq %rbp
|
||||||
# mov RBP, RSP
|
# movq %rsp, %rbp
|
||||||
# Source line: 1
|
# ; Function *; {
|
||||||
# vmulss XMM0, XMM0, XMM0 # Scalar single precision multiply (AVX)
|
# ; Location: float.jl:398
|
||||||
# pop RBP
|
# vmulss %xmm0, %xmm0, %xmm0
|
||||||
# ret
|
# ;}
|
||||||
|
# popq %rbp
|
||||||
|
# retq
|
||||||
|
# nopw (%rax,%rax)
|
||||||
|
# ;}
|
||||||
|
|
||||||
code_native(square_area, (Float64,))
|
code_native(square_area, (Float64,))
|
||||||
# .section __TEXT,__text,regular,pure_instructions
|
# .text
|
||||||
# Filename: none
|
# ; Function square_area {
|
||||||
# Source line: 1
|
# ; Location: REPL[49]:1
|
||||||
# push RBP
|
# pushq %rbp
|
||||||
# mov RBP, RSP
|
# movq %rsp, %rbp
|
||||||
# Source line: 1
|
# ; Function *; {
|
||||||
# vmulsd XMM0, XMM0, XMM0 # Scalar double precision multiply (AVX)
|
# ; Location: float.jl:399
|
||||||
# pop RBP
|
# vmulsd %xmm0, %xmm0, %xmm0
|
||||||
# ret
|
# ;}
|
||||||
#
|
# popq %rbp
|
||||||
# 注意 只要参数中又浮点类型，Julia 就使用浮点指令
|
# retq
|
||||||
|
# nopw (%rax,%rax)
|
||||||
|
# ;}
|
||||||
|
|
||||||
|
# 注意！只要参数中有浮点数，Julia 就会使用浮点指令
|
||||||
# 让我们计算一下圆的面积
|
# 让我们计算一下圆的面积
|
||||||
circle_area(r) = pi * r * r # circle_area (generic function with 1 method)
|
circle_area(r) = pi * r * r # => circle_area (generic function with 1 method)
|
||||||
circle_area(5) # 78.53981633974483
|
circle_area(5) # => 78.53981633974483
|
||||||
|
|
||||||
code_native(circle_area, (Int32,))
|
code_native(circle_area, (Int32,))
|
||||||
# .section __TEXT,__text,regular,pure_instructions
|
# .text
|
||||||
# Filename: none
|
# ; Function circle_area {
|
||||||
# Source line: 1
|
# ; Location: REPL[53]:1
|
||||||
# push RBP
|
# pushq %rbp
|
||||||
# mov RBP, RSP
|
# movq %rsp, %rbp
|
||||||
# Source line: 1
|
# ; Function *; {
|
||||||
# vcvtsi2sd XMM0, XMM0, EDI # Load integer (r) from memory
|
# ; Location: operators.jl:502
|
||||||
# movabs RAX, 4593140240 # Load pi
|
# ; Function *; {
|
||||||
# vmulsd XMM1, XMM0, QWORD PTR [RAX] # pi * r
|
# ; Location: promotion.jl:314
|
||||||
# vmulsd XMM0, XMM0, XMM1 # (pi * r) * r
|
# ; Function promote; {
|
||||||
# pop RBP
|
# ; Location: promotion.jl:284
|
||||||
# ret
|
# ; Function _promote; {
|
||||||
#
|
# ; Location: promotion.jl:261
|
||||||
|
# ; Function convert; {
|
||||||
|
# ; Location: number.jl:7
|
||||||
|
# ; Function Type; {
|
||||||
|
# ; Location: float.jl:60
|
||||||
|
# vcvtsi2sdl %ecx, %xmm0, %xmm0
|
||||||
|
# movabsq $532051920, %rax # imm = 0x1FB677D0
|
||||||
|
# ;}}}}}
|
||||||
|
# ; Function *; {
|
||||||
|
# ; Location: float.jl:399
|
||||||
|
# vmulsd (%rax), %xmm0, %xmm1
|
||||||
|
# vmulsd %xmm0, %xmm1, %xmm0
|
||||||
|
# ;}}
|
||||||
|
# popq %rbp
|
||||||
|
# retq
|
||||||
|
# nopl (%rax)
|
||||||
|
# ;}
|
||||||
|
|
||||||
code_native(circle_area, (Float64,))
|
code_native(circle_area, (Float64,))
|
||||||
# .section __TEXT,__text,regular,pure_instructions
|
# .text
|
||||||
# Filename: none
|
# ; Function circle_area {
|
||||||
# Source line: 1
|
# ; Location: REPL[53]:1
|
||||||
# push RBP
|
# pushq %rbp
|
||||||
# mov RBP, RSP
|
# movq %rsp, %rbp
|
||||||
# movabs RAX, 4593140496
|
# movabsq $532052040, %rax # imm = 0x1FB67848
|
||||||
# Source line: 1
|
# ; Function *; {
|
||||||
# vmulsd XMM1, XMM0, QWORD PTR [RAX]
|
# ; Location: operators.jl:502
|
||||||
# vmulsd XMM0, XMM1, XMM0
|
# ; Function *; {
|
||||||
# pop RBP
|
# ; Location: promotion.jl:314
|
||||||
# ret
|
# ; Function *; {
|
||||||
#
|
# ; Location: float.jl:399
|
||||||
|
# vmulsd (%rax), %xmm0, %xmm1
|
||||||
|
# ;}}}
|
||||||
|
# ; Function *; {
|
||||||
|
# ; Location: float.jl:399
|
||||||
|
# vmulsd %xmm0, %xmm1, %xmm0
|
||||||
|
# ;}
|
||||||
|
# popq %rbp
|
||||||
|
# retq
|
||||||
|
# nopl (%rax,%rax)
|
||||||
|
# ;}
|
||||||
```
|
```
|
||||||
|
|||||||
Reference in New Issue
Block a user