A = rand(10,300)

b = rand(10)
x = A \ b
B = A' * A
erf(eigvals(B)) - 2x.^2 + 4x - 6

cos(big(3 + 4im))

matchall(r"\s[a-z]+", "α is a Grëék letter") # regex search of a Unicode string

α̂₂′ = 7
ħ = 6.62606957e-34 / 2π
ẋ = ħ * α̂₂′

≪(x,y) = x < 0.1*y
50 ≪ 100, 5 ≪ 100, 5 ≤ 50

const ⊗ = kron
eye(2,2) ⊗ rand(2,2)

# verbose form:
function foo(x)
    return x + 1
end

# one-line form:
foo(x) = x + 1

# anonymous function
x -> x + 1

foo(3) # compiles foo for Int arguments

foo(7) # re-uses compiled foo(Int)

foo(7.3) # compiles a different version for Float64 arguments

foo([1,2,7,9]) # compiles a different version for Array{Int,1} arguments

code_typed(foo, (Int,)) # julia expressions with type annotations

code_native(foo, (Int,))  # assembly code