Ensure code blocks in doc are doctests or @repl

Author: goerz

docs/src/mutable.md

@@ -1,11 +1,18 @@
+```@meta
+DocTestSetup = quote
+    using Bijections
+end
+```
+
 # [Bijections for Mutable Structures](@id mutable)
 
 ## Mutating keys/values can lead to corruption
 
 The safest use of a `Bijection` is when the keys and values  are immutable.
 If a mutable key or value in a `Bijection` is altered, the bijective property
 can be compromised. Here is an example:
-```
+
+```jldoctest
 julia> b = Bijection{Int, Vector{Int}}();
 
 julia> b[1] = [1,2,3]
@@ -42,7 +49,8 @@ In case none of these is a viable option, we provide the following additional al
 ## Keys/values as objects
 
 The issue in the example presented above is that distinct Julia objects may be equal, but not the same object. For example:
-```
+
+```jldoctest
 julia> v = [1,2,3];
 
 julia> w = [1,2,3];
@@ -55,13 +63,16 @@ false
 ```
 
 We may wish to create a `Bijection` in which the keys or values are permitted to be equal, but are distinct objects. Julia's `IdDict` is a variation of `Dict` in which keys/values are considered different if they are distinct object (even if they hold the same data). To replicate this behavior in a `Bijection` use this longer form constructor:
-```
+
+```julia
 Bijection{K, V, IdDict{K,V}, IdDict{V,K}}()
 ```
+
 where `K` is the type of the keys and `V` is the type of the values.
 
 For example:
-```
+
+```jldoctest
 julia> b = Bijection{Vector{Int}, String, IdDict{Vector{Int},String}, IdDict{String,Vector{Int}}}();
 
 julia> b[ [1,2,3] ] = "alpha";

docs/src/operations.md

@@ -1,3 +1,9 @@
+```@meta
+DocTestSetup = quote
+    using Bijections
+end
+```
+
 # Operations
 
 
@@ -9,12 +15,14 @@ There are two functions that take a `Bijection` and return a new
 [`inv`](@ref) and [`active_inv`](@ref).
 
 ### Independent inverse: `inv`
+
 Given a `Bijection` `b`, calling `inv(b)` creates a new `Bijection`
 that is the inverse of `b`. The new `Bijection` is completely independent
 of the original, `b`. Changes to one do not affect the other:
-```
+
+```jldoctest
 julia> b = Bijection{Int,String}()
-Bijection Dict{Int64, String}()
+Bijection{Int64, String, Dict{Int64, String}, Dict{String, Int64}}()
 
 julia> b[1] = "alpha"
 "alpha"
@@ -23,7 +31,7 @@ julia> b[2] = "beta"
 "beta"
 
 julia> bb = inv(b)
-Bijection Dict{String, Int64} with 2 entries:
+Bijection{String, Int64, Dict{String, Int64}, Dict{Int64, String}} with 2 entries:
   "alpha" => 1
   "beta"  => 2
 
@@ -38,6 +46,7 @@ julia> b[3] = "gamma"
 
 julia> bb["gamma"]
 ERROR: KeyError: key "gamma" not found
+[...]
 ```
 
 ### Active inverse: `active_inv`
@@ -47,9 +56,9 @@ case the original and the inverse are actively tied together.
 That is, modification of one immediately affects the other.
 The two `Bijection`s remain inverses no matter how either is modified.
 
-```
+```jldoctest
 julia> b = Bijection{Int,String}()
-Bijection Dict{Int64, String}()
+Bijection{Int64, String, Dict{Int64, String}, Dict{String, Int64}}()
 
 julia> b[1] = "alpha"
 "alpha"
@@ -58,7 +67,7 @@ julia> b[2] = "beta"
 "beta"
 
 julia> bb = active_inv(b)
-Bijection Dict{String, Int64} with 2 entries:
+Bijection{String, Int64, Dict{String, Int64}, Dict{Int64, String}} with 2 entries:
   "alpha" => 1
   "beta"  => 2
 
@@ -73,10 +82,10 @@ julia> bb["gamma"]
 
 `Bijection`s can be used in a `for` statement just like Julia
 dictionaries:
-```
-julia> for (x,y) in b; println("$x --> $y"); end
-2 --> beta
-3 --> gamma
-1 --> alpha
-```
 
+```@repl example
+# The order of iteration is not guaranteed, so this can't be a doctest # hide
+using Bijections # hide
+b = Bijection(1 => "alpha", 2 => "beta", 3 => "gamma");
+for (x, y) in b; println("$x --> $y"); end
+```