June 2018 Update

Task/Execute-a-Markov-algorithm/Julia/execute-a-markov-algorithm-1.julia

@@ -0,0 +1,48 @@
+module MarkovAlgos
+
+struct MarkovRule{F,T}
+    patt::F
+    repl::T
+    term::Bool
+end
+
+isterminating(r::MarkovRule) = r.term
+Base.show(io::IO, rule::MarkovRule) =
+    print(io, rule.patt, " → ", isterminating(rule) ? "." : "", rule.repl)
+function Base.convert(::Type{MarkovRule}, s::AbstractString)
+    rmatch = match(r"^(.+)\s+->\s*(\.)?(.*)?$", s)
+    if rmatch ≡ nothing || isempty(rmatch.captures)
+        throw(ParseError("not valid rule: " * s))
+    end
+    patt, term, repl = rmatch.captures
+    return MarkovRule(patt, repl ≢ nothing ? repl : "", term ≢ nothing)
+end
+
+function ruleset(file::Union{AbstractString,IO})
+    ruleset = Vector{MarkovRule}(0)
+    for line in eachline(file)
+        ismatch(r"(^#|^\s*$)", line) || push!(ruleset, MarkovRule(line))
+    end
+    return ruleset
+end
+
+apply(text::AbstractString, rule::MarkovRule) = replace(text, rule.patt, rule.repl)
+function apply(file::Union{AbstractString,IO}, ruleset::AbstractVector{<:MarkovRule})
+    text = readstring(file)
+    redo = !isempty(text)
+    while redo
+        matchrule = false
+        for rule in ruleset
+            if contains(text, rule.patt)
+                matchrule = true
+                text = apply(text, rule)
+                redo = !isterminating(rule)
+                break
+            end
+        end
+        redo = redo && matchrule
+    end
+    return text
+end
+
+end  # module MarkovAlgos

Task/Execute-a-Markov-algorithm/Julia/execute-a-markov-algorithm-2.julia

@@ -0,0 +1,11 @@
+include("module.jl")
+
+let rulesets = @.("data/markovrules0" * string(1:5) * ".txt"),
+    ruletest = @.("data/markovtest0" * string(1:5) * ".txt")
+    for i in eachindex(rulesets, ruletest)
+        rules = MarkovAlgos.ruleset(rulesets[i])
+        println("# Example n.$i")
+        println("Original:\n", readstring(ruletest[i]))
+        println("Transformed:\n", MarkovAlgos.apply(ruletest[i], rules))
+    end
+end