Documentation

DFA.fs

@@ -8,10 +8,16 @@ type State = { name: String }
 /// A deterministic finite automaton
 /// 
 type DFA = {
+    /// All possible characters
     sigma: Char list
+    /// All possible states
     states: State list
+    /// All possible transitions
     delta: State -> Char -> State
+    /// The state this DFA begins in
     beginState: State
+    /// The states in which this DFA accepts
+    /// the word
     acceptingStates: State list
 }
 
@@ -43,14 +49,19 @@ let validateDFA (dfa:DFA) =
     allAcceptingStatesAreStates ||
     deltaIsComplete
 
+/// Returns the state the DFA is in after
+/// reading this character
 let processChar (dfa: DFA) (state: State) (char: Char) =
     dfa.delta state char
 
+/// Returns the state the DFA is in after
+/// reading this character array
 let rec processCharArray (dfa: DFA) (state: State) (charArr: Char list) =
     match charArr with
     | [] -> state
     | head :: tail -> processCharArray dfa (processChar dfa state head) tail
 
+/// Returns whether the DFA accepts this word
 let acceptsWord (dfa: DFA) (word: String) =
     dfa.acceptingStates
     |> List.contains (processCharArray dfa dfa.beginState (Seq.toList word))

NFA.fs

@@ -6,16 +6,26 @@ type State = { name: String }
 
 /// A non-deterministic finite automaton
 type NFA = {
+    /// All possible characters
     sigma: Char list
+    /// All possible states
     states: State list
+    /// All possible transitions
     delta: State -> Char -> State list
+    /// The state this NFA begins in
     beginState: State
+    /// The states in which this NFA accepts
+    /// the word
     acceptingStates: State list
 }
 
+/// Returns a list of possible states after this charater
+/// was read
 let processChar (nfa: NFA) (state: State) (char: Char) =
     nfa.delta state char
 
+/// Returns a list of possible states after this character
+/// list was read
 let rec processCharArray (nfa: NFA) (states: State list) (charArr: Char list) : State list =
     match charArr with
     | [] -> states
@@ -23,16 +33,23 @@ let rec processCharArray (nfa: NFA) (states: State list) (charArr: Char list) :
         processCharArray
             nfa
             (
+                // Look at all states
                 states
+                // Where are we going to from each state
+                // if we read this character
                 |> List.map (fun x -> processChar nfa x head)
+                // Which entries are not empty
                 |> List.filter (List.isEmpty >> not)
+                // If there are no states left,
+                // return an empty list
                 |> (fun x -> 
-                    if not (List.isEmpty x) then
-                        List.reduce List.append x 
-                    else [])
+                        if not (List.isEmpty x) then
+                            List.reduce List.append x 
+                        else [])
             )
             tail
 
+/// Returns whether this NFA accepts this word
 let acceptsWord nfa word = 
     match processCharArray nfa [nfa.beginState] (Seq.toList word) with
     | [] -> false