Move docs inline from helpdb/Base.jl

Author: xorJane

base/abstractarray.jl

@@ -127,11 +127,41 @@ _length(A) = length(A)
 endof(a::AbstractArray) = length(a)
 first(a::AbstractArray) = a[first(eachindex(a))]
 
+"""
+    first(coll)
+
+Get the first element of an iterable collection. Returns the start point of a
+`Range` even if it is empty.
+
+```jldoctest
+julia> first(2:2:10)
+2
+
+julia> first([1; 2; 3; 4])
+1
+```
+"""
 function first(itr)
     state = start(itr)
     done(itr, state) && throw(ArgumentError("collection must be non-empty"))
     next(itr, state)[1]
 end
+
+"""
+    last(coll)
+
+Get the last element of an ordered collection, if it can be computed in O(1) time. This is
+accomplished by calling [`endof`](@ref) to get the last index. Returns the end
+point of a `Range` even if it is empty.
+
+```jldoctest
+julia> last(1:2:10)
+9
+
+julia> last([1; 2; 3; 4])
+4
+```
+"""
 last(a) = a[end]
 
 """

base/bitarray.jl

@@ -1301,6 +1301,23 @@ function (|)(B::BitArray, x::Bool)
 end
 (|)(x::Bool, B::BitArray) = B | x
 
+"""
+    xor(x, y)
+    ⊻(x, y)
+
+Bitwise exclusive or of `x` and `y`.  The infix operation
+`a ⊻ b` is a synonym for `xor(a,b)`, and
+`⊻` can be typed by tab-completing `\\xor`
+or `\\veebar` in the Julia REPL.
+
+```jldoctest
+julia> [true; true; false] ⊻ [true; false; false]
+3-element Array{Bool,1}:
+ false
+  true
+ false
+```
+"""
 function xor(B::BitArray, x::Bool)
     x ? ~B : copy(B)
 end

base/bool.jl

@@ -14,6 +14,23 @@ typemax(::Type{Bool}) = true
 
 ## boolean operations ##
 
+"""
+    !(x)
+
+Boolean not.
+
+```jldoctest
+julia> !true
+false
+
+julia> !false
+true
+
+julia> ![true false true]
+1×3 Array{Bool,2}:
+ false  true  false
+```
+"""
 function !(x::Bool)
     ## We need a better heuristic to detect this automatically
     @_pure_meta

base/complex.jl

@@ -75,6 +75,19 @@ real(T::Type) = typeof(real(zero(T)))
 real{T<:Real}(::Type{T}) = T
 real{T<:Real}(::Type{Complex{T}}) = T
 
+"""
+    isreal(x) -> Bool
+
+Test whether `x` or all its elements are numerically equal to some real number.
+
+```jldoctest
+julia> isreal(5.)
+true
+
+julia> isreal([4.; complex(0,1)])
+false
+```
+"""
 isreal(x::Real) = true
 isreal(z::Complex) = iszero(imag(z))
 """

base/dict.jl

@@ -283,6 +283,23 @@ function sizehint!(d::Dict, newsz)
     rehash!(d, newsz)
 end
 
+"""
+    empty!(collection) -> collection
+
+Remove all elements from a `collection`.
+
+```jldoctest
+julia> A = Dict("a" => 1, "b" => 2)
+Dict{String,Int64} with 2 entries:
+  "b" => 2
+  "a" => 1
+
+julia> empty!(A);
+
+julia> A
+Dict{String,Int64} with 0 entries
+```
+"""
 function empty!{K,V}(h::Dict{K,V})
     fill!(h.slots, 0x0)
     sz = length(h.slots)