summaryrefslogtreecommitdiffhomepage
path: root/julia.html.markdown
diff options
context:
space:
mode:
Diffstat (limited to 'julia.html.markdown')
-rw-r--r--julia.html.markdown318
1 files changed, 159 insertions, 159 deletions
diff --git a/julia.html.markdown b/julia.html.markdown
index b8e24b39..8245e616 100644
--- a/julia.html.markdown
+++ b/julia.html.markdown
@@ -21,58 +21,58 @@ This is based on the current development version of Julia, as of October 18th, 2
# Everything in Julia is a expression.
# There are several basic types of numbers.
-3 #=> 3 (Int64)
-3.2 #=> 3.2 (Float64)
-2 + 1im #=> 2 + 1im (Complex{Int64})
-2//3 #=> 2//3 (Rational{Int64})
+3 # => 3 (Int64)
+3.2 # => 3.2 (Float64)
+2 + 1im # => 2 + 1im (Complex{Int64})
+2//3 # => 2//3 (Rational{Int64})
# All of the normal infix operators are available.
-1 + 1 #=> 2
-8 - 1 #=> 7
-10 * 2 #=> 20
-35 / 5 #=> 7.0
-5 / 2 #=> 2.5 # dividing an Int by an Int always results in a Float
-div(5, 2) #=> 2 # for a truncated result, use div
-5 \ 35 #=> 7.0
-2 ^ 2 #=> 4 # power, not bitwise xor
-12 % 10 #=> 2
+1 + 1 # => 2
+8 - 1 # => 7
+10 * 2 # => 20
+35 / 5 # => 7.0
+5 / 2 # => 2.5 # dividing an Int by an Int always results in a Float
+div(5, 2) # => 2 # for a truncated result, use div
+5 \ 35 # => 7.0
+2 ^ 2 # => 4 # power, not bitwise xor
+12 % 10 # => 2
# Enforce precedence with parentheses
-(1 + 3) * 2 #=> 8
+(1 + 3) * 2 # => 8
# Bitwise Operators
-~2 #=> -3 # bitwise not
-3 & 5 #=> 1 # bitwise and
-2 | 4 #=> 6 # bitwise or
-2 $ 4 #=> 6 # bitwise xor
-2 >>> 1 #=> 1 # logical shift right
-2 >> 1 #=> 1 # arithmetic shift right
-2 << 1 #=> 4 # logical/arithmetic shift left
+~2 # => -3 # bitwise not
+3 & 5 # => 1 # bitwise and
+2 | 4 # => 6 # bitwise or
+2 $ 4 # => 6 # bitwise xor
+2 >>> 1 # => 1 # logical shift right
+2 >> 1 # => 1 # arithmetic shift right
+2 << 1 # => 4 # logical/arithmetic shift left
# You can use the bits function to see the binary representation of a number.
bits(12345)
-#=> "0000000000000000000000000000000000000000000000000011000000111001"
+# => "0000000000000000000000000000000000000000000000000011000000111001"
bits(12345.0)
-#=> "0100000011001000000111001000000000000000000000000000000000000000"
+# => "0100000011001000000111001000000000000000000000000000000000000000"
# Boolean values are primitives
true
false
# Boolean operators
-!true #=> false
-!false #=> true
-1 == 1 #=> true
-2 == 1 #=> false
-1 != 1 #=> false
-2 != 1 #=> true
-1 < 10 #=> true
-1 > 10 #=> false
-2 <= 2 #=> true
-2 >= 2 #=> true
+!true # => false
+!false # => true
+1 == 1 # => true
+2 == 1 # => false
+1 != 1 # => false
+2 != 1 # => true
+1 < 10 # => true
+1 > 10 # => false
+2 <= 2 # => true
+2 >= 2 # => true
# Comparisons can be chained
-1 < 2 < 3 #=> true
-2 < 3 < 2 #=> false
+1 < 2 < 3 # => true
+2 < 3 < 2 # => false
# Strings are created with "
"This is a string."
@@ -81,12 +81,12 @@ false
'a'
# A string can be indexed like an array of characters
-"This is a string"[1] #=> 'T' # Julia indexes from 1
+"This is a string"[1] # => 'T' # Julia indexes from 1
# However, this is will not work well for UTF8 strings,
# so iterating over strings is recommended (map, for loops, etc).
# $ can be used for string interpolation:
-"2 + 2 = $(2 + 2)" #=> "2 + 2 = 4"
+"2 + 2 = $(2 + 2)" # => "2 + 2 = 4"
# You can put any Julia expression inside the parenthesis.
# Another way to format strings is the printf macro.
@@ -100,24 +100,24 @@ println("I'm Julia. Nice to meet you!")
####################################################
# You don't declare variables before assigning to them.
-some_var = 5 #=> 5
-some_var #=> 5
+some_var = 5 # => 5
+some_var # => 5
# Accessing a previously unassigned variable is an error
try
- some_other_var #=> ERROR: some_other_var not defined
+ some_other_var # => ERROR: some_other_var not defined
catch e
println(e)
end
# Variable names start with a letter.
# After that, you can use letters, digits, underscores, and exclamation points.
-SomeOtherVar123! = 6 #=> 6
+SomeOtherVar123! = 6 # => 6
# You can also use unicode characters
-☃ = 8 #=> 8
+☃ = 8 # => 8
# These are especially handy for mathematical notation
-2 * π #=> 6.283185307179586
+2 * π # => 6.283185307179586
# A note on naming conventions in Julia:
#
@@ -133,49 +133,49 @@ SomeOtherVar123! = 6 #=> 6
# functions are sometimes called mutating functions or in-place functions.
# Arrays store a sequence of values indexed by integers 1 through n:
-a = Int64[] #=> 0-element Int64 Array
+a = Int64[] # => 0-element Int64 Array
# 1-dimensional array literals can be written with comma-separated values.
-b = [4, 5, 6] #=> 3-element Int64 Array: [4, 5, 6]
-b[1] #=> 4
-b[end] #=> 6
+b = [4, 5, 6] # => 3-element Int64 Array: [4, 5, 6]
+b[1] # => 4
+b[end] # => 6
# 2-dimentional arrays use space-separated values and semicolon-separated rows.
-matrix = [1 2; 3 4] #=> 2x2 Int64 Array: [1 2; 3 4]
+matrix = [1 2; 3 4] # => 2x2 Int64 Array: [1 2; 3 4]
# Add stuff to the end of a list with push! and append!
-push!(a,1) #=> [1]
-push!(a,2) #=> [1,2]
-push!(a,4) #=> [1,2,4]
-push!(a,3) #=> [1,2,4,3]
-append!(a,b) #=> [1,2,4,3,4,5,6]
+push!(a,1) # => [1]
+push!(a,2) # => [1,2]
+push!(a,4) # => [1,2,4]
+push!(a,3) # => [1,2,4,3]
+append!(a,b) # => [1,2,4,3,4,5,6]
# Remove from the end with pop
-pop!(b) #=> 6 and b is now [4,5]
+pop!(b) # => 6 and b is now [4,5]
# Let's put it back
push!(b,6) # b is now [4,5,6] again.
-a[1] #=> 1 # remember that Julia indexes from 1, not 0!
+a[1] # => 1 # remember that Julia indexes from 1, not 0!
# end is a shorthand for the last index. It can be used in any
# indexing expression
-a[end] #=> 6
+a[end] # => 6
# we also have shift and unshift
-shift!(a) #=> 1 and a is now [2,4,3,4,5,6]
-unshift!(a,7) #=> [7,2,4,3,4,5,6]
+shift!(a) # => 1 and a is now [2,4,3,4,5,6]
+unshift!(a,7) # => [7,2,4,3,4,5,6]
# Function names that end in exclamations points indicate that they modify
# their argument.
-arr = [5,4,6] #=> 3-element Int64 Array: [5,4,6]
-sort(arr) #=> [4,5,6]; arr is still [5,4,6]
-sort!(arr) #=> [4,5,6]; arr is now [4,5,6]
+arr = [5,4,6] # => 3-element Int64 Array: [5,4,6]
+sort(arr) # => [4,5,6]; arr is still [5,4,6]
+sort!(arr) # => [4,5,6]; arr is now [4,5,6]
# Looking out of bounds is a BoundsError
try
- a[0] #=> ERROR: BoundsError() in getindex at array.jl:270
- a[end+1] #=> ERROR: BoundsError() in getindex at array.jl:270
+ a[0] # => ERROR: BoundsError() in getindex at array.jl:270
+ a[end+1] # => ERROR: BoundsError() in getindex at array.jl:270
catch e
println(e)
end
@@ -185,110 +185,110 @@ end
# inside the julia folder to find these files.
# You can initialize arrays from ranges
-a = [1:5] #=> 5-element Int64 Array: [1,2,3,4,5]
+a = [1:5] # => 5-element Int64 Array: [1,2,3,4,5]
# You can look at ranges with slice syntax.
-a[1:3] #=> [1, 2, 3]
-a[2:] #=> [2, 3, 4, 5]
-a[2:end] #=> [2, 3, 4, 5]
+a[1:3] # => [1, 2, 3]
+a[2:] # => [2, 3, 4, 5]
+a[2:end] # => [2, 3, 4, 5]
# Remove elements from an array by index with splice!
arr = [3,4,5]
-splice!(arr,2) #=> 4 ; arr is now [3,5]
+splice!(arr,2) # => 4 ; arr is now [3,5]
# Concatenate lists with append!
b = [1,2,3]
append!(a,b) # Now a is [1, 2, 3, 4, 5, 1, 2, 3]
# Check for existence in a list with in
-in(1, a) #=> true
+in(1, a) # => true
# Examine the length with length
-length(a) #=> 8
+length(a) # => 8
# Tuples are immutable.
-tup = (1, 2, 3) #=> (1,2,3) # an (Int64,Int64,Int64) tuple.
-tup[1] #=> 1
+tup = (1, 2, 3) # => (1,2,3) # an (Int64,Int64,Int64) tuple.
+tup[1] # => 1
try:
- tup[1] = 3 #=> ERROR: no method setindex!((Int64,Int64,Int64),Int64,Int64)
+ tup[1] = 3 # => ERROR: no method setindex!((Int64,Int64,Int64),Int64,Int64)
catch e
println(e)
end
# Many list functions also work on tuples
-length(tup) #=> 3
-tup[1:2] #=> (1,2)
-in(2, tup) #=> true
+length(tup) # => 3
+tup[1:2] # => (1,2)
+in(2, tup) # => true
# You can unpack tuples into variables
-a, b, c = (1, 2, 3) #=> (1,2,3) # a is now 1, b is now 2 and c is now 3
+a, b, c = (1, 2, 3) # => (1,2,3) # a is now 1, b is now 2 and c is now 3
# Tuples are created even if you leave out the parentheses
-d, e, f = 4, 5, 6 #=> (4,5,6)
+d, e, f = 4, 5, 6 # => (4,5,6)
# A 1-element tuple is distinct from the value it contains
-(1,) == 1 #=> false
-(1) == 1 #=> true
+(1,) == 1 # => false
+(1) == 1 # => true
# Look how easy it is to swap two values
-e, d = d, e #=> (5,4) # d is now 5 and e is now 4
+e, d = d, e # => (5,4) # d is now 5 and e is now 4
# Dictionaries store mappings
-empty_dict = Dict() #=> Dict{Any,Any}()
+empty_dict = Dict() # => Dict{Any,Any}()
# You can create a dictionary using a literal
filled_dict = ["one"=> 1, "two"=> 2, "three"=> 3]
# => Dict{ASCIIString,Int64}
# Look up values with []
-filled_dict["one"] #=> 1
+filled_dict["one"] # => 1
# Get all keys
keys(filled_dict)
-#=> KeyIterator{Dict{ASCIIString,Int64}}(["three"=>3,"one"=>1,"two"=>2])
+# => KeyIterator{Dict{ASCIIString,Int64}}(["three"=>3,"one"=>1,"two"=>2])
# Note - dictionary keys are not sorted or in the order you inserted them.
# Get all values
values(filled_dict)
-#=> ValueIterator{Dict{ASCIIString,Int64}}(["three"=>3,"one"=>1,"two"=>2])
+# => ValueIterator{Dict{ASCIIString,Int64}}(["three"=>3,"one"=>1,"two"=>2])
# Note - Same as above regarding key ordering.
# Check for existence of keys in a dictionary with in, haskey
-in(("one", 1), filled_dict) #=> true
-in(("two", 3), filled_dict) #=> false
-haskey(filled_dict, "one") #=> true
-haskey(filled_dict, 1) #=> false
+in(("one", 1), filled_dict) # => true
+in(("two", 3), filled_dict) # => false
+haskey(filled_dict, "one") # => true
+haskey(filled_dict, 1) # => false
# Trying to look up a non-existant key will raise an error
try
- filled_dict["four"] #=> ERROR: key not found: four in getindex at dict.jl:489
+ filled_dict["four"] # => ERROR: key not found: four in getindex at dict.jl:489
catch e
println(e)
end
# Use the get method to avoid that error by providing a default value
# get(dictionary,key,default_value)
-get(filled_dict,"one",4) #=> 1
-get(filled_dict,"four",4) #=> 4
+get(filled_dict,"one",4) # => 1
+get(filled_dict,"four",4) # => 4
# Use Sets to represent collections of unordered, unique values
-empty_set = Set() #=> Set{Any}()
+empty_set = Set() # => Set{Any}()
# Initialize a set with values
-filled_set = Set(1,2,2,3,4) #=> Set{Int64}(1,2,3,4)
+filled_set = Set(1,2,2,3,4) # => Set{Int64}(1,2,3,4)
# Add more values to a set
-push!(filled_set,5) #=> Set{Int64}(5,4,2,3,1)
+push!(filled_set,5) # => Set{Int64}(5,4,2,3,1)
# Check if the values are in the set
-in(2, filled_set) #=> true
-in(10, filled_set) #=> false
+in(2, filled_set) # => true
+in(10, filled_set) # => false
# There are functions for set intersection, union, and difference.
-other_set = Set(3, 4, 5, 6) #=> Set{Int64}(6,4,5,3)
-intersect(filled_set, other_set) #=> Set{Int64}(3,4,5)
-union(filled_set, other_set) #=> Set{Int64}(1,2,3,4,5,6)
-setdiff(Set(1,2,3,4),Set(2,3,5)) #=> Set{Int64}(1,4)
+other_set = Set(3, 4, 5, 6) # => Set{Int64}(6,4,5,3)
+intersect(filled_set, other_set) # => Set{Int64}(3,4,5)
+union(filled_set, other_set) # => Set{Int64}(1,2,3,4,5,6)
+setdiff(Set(1,2,3,4),Set(2,3,5)) # => Set{Int64}(1,4)
####################################################
@@ -306,7 +306,7 @@ elseif some_var < 10 # This elseif clause is optional.
else # The else clause is optional too.
println("some_var is indeed 10.")
end
-#=> prints "some var is smaller than 10"
+# => prints "some var is smaller than 10"
# For loops iterate over iterables.
@@ -363,7 +363,7 @@ try
catch e
println("caught it $e")
end
-#=> caught it ErrorException("help")
+# => caught it ErrorException("help")
####################################################
@@ -381,7 +381,7 @@ function add(x, y)
x + y
end
-add(5, 6) #=> 11 after printing out "x is 5 and y is 6"
+add(5, 6) # => 11 after printing out "x is 5 and y is 6"
# You can define functions that take a variable number of
# positional arguments
@@ -389,20 +389,20 @@ function varargs(args...)
return args
# use the keyword return to return anywhere in the function
end
-#=> varargs (generic function with 1 method)
+# => varargs (generic function with 1 method)
-varargs(1,2,3) #=> (1,2,3)
+varargs(1,2,3) # => (1,2,3)
# The ... is called a splat.
# We just used it in a function definition.
# It can also be used in a fuction call,
# where it will splat an Array or Tuple's contents into the argument list.
-Set([1,2,3]) #=> Set{Array{Int64,1}}([1,2,3]) # produces a Set of Arrays
-Set([1,2,3]...) #=> Set{Int64}(1,2,3) # this is equivalent to Set(1,2,3)
+Set([1,2,3]) # => Set{Array{Int64,1}}([1,2,3]) # produces a Set of Arrays
+Set([1,2,3]...) # => Set{Int64}(1,2,3) # this is equivalent to Set(1,2,3)
-x = (1,2,3) #=> (1,2,3)
-Set(x) #=> Set{(Int64,Int64,Int64)}((1,2,3)) # a Set of Tuples
-Set(x...) #=> Set{Int64}(2,3,1)
+x = (1,2,3) # => (1,2,3)
+Set(x) # => Set{(Int64,Int64,Int64)}((1,2,3)) # a Set of Tuples
+Set(x...) # => Set{Int64}(2,3,1)
# You can define functions with optional positional arguments
@@ -410,12 +410,12 @@ function defaults(a,b,x=5,y=6)
return "$a $b and $x $y"
end
-defaults('h','g') #=> "h g and 5 6"
-defaults('h','g','j') #=> "h g and j 6"
-defaults('h','g','j','k') #=> "h g and j k"
+defaults('h','g') # => "h g and 5 6"
+defaults('h','g','j') # => "h g and j 6"
+defaults('h','g','j','k') # => "h g and j k"
try
- defaults('h') #=> ERROR: no method defaults(Char,)
- defaults() #=> ERROR: no methods defaults()
+ defaults('h') # => ERROR: no method defaults(Char,)
+ defaults() # => ERROR: no methods defaults()
catch e
println(e)
end
@@ -425,9 +425,9 @@ function keyword_args(;k1=4,name2="hello") # note the ;
return ["k1"=>k1,"name2"=>name2]
end
-keyword_args(name2="ness") #=> ["name2"=>"ness","k1"=>4]
-keyword_args(k1="mine") #=> ["k1"=>"mine","name2"=>"hello"]
-keyword_args() #=> ["name2"=>"hello","k1"=>4]
+keyword_args(name2="ness") # => ["name2"=>"ness","k1"=>4]
+keyword_args(k1="mine") # => ["k1"=>"mine","name2"=>"hello"]
+keyword_args() # => ["name2"=>"hello","k1"=>4]
# You can combine all kinds of arguments in the same function
function all_the_args(normal_arg, optional_positional_arg=2; keyword_arg="foo")
@@ -451,7 +451,7 @@ function create_adder(x)
end
# This is "stabby lambda syntax" for creating anonymous functions
-(x -> x > 2)(3) #=> true
+(x -> x > 2)(3) # => true
# This function is identical to create_adder implementation above.
function create_adder(x)
@@ -467,16 +467,16 @@ function create_adder(x)
end
add_10 = create_adder(10)
-add_10(3) #=> 13
+add_10(3) # => 13
# There are built-in higher order functions
-map(add_10, [1,2,3]) #=> [11, 12, 13]
-filter(x -> x > 5, [3, 4, 5, 6, 7]) #=> [6, 7]
+map(add_10, [1,2,3]) # => [11, 12, 13]
+filter(x -> x > 5, [3, 4, 5, 6, 7]) # => [6, 7]
# We can use list comprehensions for nicer maps
-[add_10(i) for i=[1, 2, 3]] #=> [11, 12, 13]
-[add_10(i) for i in [1, 2, 3]] #=> [11, 12, 13]
+[add_10(i) for i=[1, 2, 3]] # => [11, 12, 13]
+[add_10(i) for i in [1, 2, 3]] # => [11, 12, 13]
####################################################
## 5. Types
@@ -485,11 +485,11 @@ filter(x -> x > 5, [3, 4, 5, 6, 7]) #=> [6, 7]
# Julia has a type system.
# Every value has a type; variables do not have types themselves.
# You can use the `typeof` function to get the type of a value.
-typeof(5) #=> Int64
+typeof(5) # => Int64
# Types are first-class values
-typeof(Int64) #=> DataType
-typeof(DataType) #=> DataType
+typeof(Int64) # => DataType
+typeof(DataType) # => DataType
# DataType is the type that represents types, including itself.
# Types are used for documentation, optimizations, and dispatch.
@@ -510,10 +510,10 @@ end
# The default constructor's arguments are the properties
# of the type, in the order they are listed in the definition
-tigger = Tiger(3.5,"orange") #=> Tiger(3.5,"orange")
+tigger = Tiger(3.5,"orange") # => Tiger(3.5,"orange")
# The type doubles as the constructor function for values of that type
-sherekhan = typeof(tigger)(5.6,"fire") #=> Tiger(5.6,"fire")
+sherekhan = typeof(tigger)(5.6,"fire") # => Tiger(5.6,"fire")
# These struct-style types are called concrete types
# They can be instantiated, but cannot have subtypes.
@@ -524,23 +524,23 @@ abstract Cat # just a name and point in the type hierarchy
# Abstract types cannot be instantiated, but can have subtypes.
# For example, Number is an abstract type
-subtypes(Number) #=> 6-element Array{Any,1}:
+subtypes(Number) # => 6-element Array{Any,1}:
# Complex{Float16}
# Complex{Float32}
# Complex{Float64}
# Complex{T<:Real}
# ImaginaryUnit
# Real
-subtypes(Cat) #=> 0-element Array{Any,1}
+subtypes(Cat) # => 0-element Array{Any,1}
# Every type has a super type; use the `super` function to get it.
-typeof(5) #=> Int64
-super(Int64) #=> Signed
-super(Signed) #=> Real
-super(Real) #=> Number
-super(Number) #=> Any
-super(super(Signed)) #=> Number
-super(Any) #=> Any
+typeof(5) # => Int64
+super(Int64) # => Signed
+super(Signed) # => Real
+super(Real) # => Number
+super(Number) # => Any
+super(super(Signed)) # => Number
+super(Any) # => Any
# All of these type, except for Int64, are abstract.
# <: is the subtyping operator
@@ -588,23 +588,23 @@ function meow(animal::Tiger)
end
# Testing the meow function
-meow(tigger) #=> "rawwr"
-meow(Lion("brown","ROAAR")) #=> "ROAAR"
-meow(Panther()) #=> "grrr"
+meow(tigger) # => "rawwr"
+meow(Lion("brown","ROAAR")) # => "ROAAR"
+meow(Panther()) # => "grrr"
# Review the local type hierarchy
-issubtype(Tiger,Cat) #=> false
-issubtype(Lion,Cat) #=> true
-issubtype(Panther,Cat) #=> true
+issubtype(Tiger,Cat) # => false
+issubtype(Lion,Cat) # => true
+issubtype(Panther,Cat) # => true
# Defining a function that takes Cats
function pet_cat(cat::Cat)
println("The cat says $(meow(cat))")
end
-pet_cat(Lion("42")) #=> prints "The cat says 42"
+pet_cat(Lion("42")) # => prints "The cat says 42"
try
- pet_cat(tigger) #=> ERROR: no method pet_cat(Tiger,)
+ pet_cat(tigger) # => ERROR: no method pet_cat(Tiger,)
catch e
println(e)
end
@@ -617,31 +617,31 @@ end
function fight(t::Tiger,c::Cat)
println("The $(t.coatcolor) tiger wins!")
end
-#=> fight (generic function with 1 method)
+# => fight (generic function with 1 method)
-fight(tigger,Panther()) #=> prints The orange tiger wins!
-fight(tigger,Lion("ROAR")) #=> prints The orange tiger wins!
+fight(tigger,Panther()) # => prints The orange tiger wins!
+fight(tigger,Lion("ROAR")) # => prints The orange tiger wins!
# Let's change the behavior when the Cat is specifically a Lion
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,Lion("ROAR")) #=> prints The green-maned lion wins!
+fight(tigger,Panther()) # => prints The orange tiger wins!
+fight(tigger,Lion("ROAR")) # => prints The green-maned lion wins!
# We don't need a Tiger in order to fight
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()) # => prints The victorious cat says grrr
try
- fight(Panther(),Lion("RAWR")) #=> ERROR: no method fight(Panther,Lion)
+ fight(Panther(),Lion("RAWR")) # => ERROR: no method fight(Panther,Lion)
catch
end
# Also let the cat go first
fight(c::Cat,l::Lion) = println("The cat beats the Lion")
-#=> Warning: New definition
+# => Warning: New definition
# fight(Cat,Lion) at none:1
# is ambiguous with
# fight(Lion,Cat) at none:2.
@@ -651,11 +651,11 @@ fight(c::Cat,l::Lion) = println("The cat beats the Lion")
#fight (generic function with 4 methods)
# This warning is because it's unclear which fight will be called in:
-fight(Lion("RAR"),Lion("brown","rarrr")) #=> prints The victorious cat says rarrr
+fight(Lion("RAR"),Lion("brown","rarrr")) # => prints The victorious cat says rarrr
# The result may be different in other versions of Julia
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(Lion("RAR"),Lion("brown","rarrr")) # => prints The lions come to a tie
# Under the hood