Add Whiley Lexer (#628)

This is a fairly simple lexer for Whiley which covers the main things (e.g.
keywords, literals, etc).

lexers/embedded/whiley.xml

@@ -0,0 +1,57 @@
+<lexer>
+  <config>
+    <name>Whiley</name>
+    <alias>whiley</alias>
+    <filename>*.whiley</filename>
+    <mime_type>text/x-whiley</mime_type>
+  </config>
+  <rules>
+    <state name="root">
+      <rule pattern="\n">
+        <token type="Text"/>
+      </rule>
+      <rule pattern="\s+">
+        <token type="Text"/>
+      </rule>
+      <rule pattern="\\\n">
+        <token type="Text"/>
+      </rule>
+      <rule pattern="/[*](.|\n)*?[*]/">
+        <token type="CommentMultiline"/>
+      </rule>
+      <rule pattern="//.*?\n">
+        <token type="CommentSingle"/>
+      </rule>      
+      <rule pattern="(function|import|from|method|property|type|with|variant)\b">
+        <token type="KeywordDeclaration"/>
+      </rule>
+      <rule pattern="(assert|assume|all|break|case|continue|debug|default|do|else|ensures|export|fail|final|for|if|in|is|native|no|new|private|protected|public|return|requires|skip|some|switch|unsafe|where|while)\b">
+        <token type="Keyword"/>
+      </rule>
+      <rule pattern="(true|false|null)\b">
+        <token type="KeywordConstant"/>
+      </rule>
+      <rule pattern="(bool|byte|int|void)\b">
+        <token type="KeywordType"/>
+      </rule>
+      <rule pattern="0b(?:_?[01])+">
+        <token type="LiteralNumberBin"/>
+      </rule>      
+      <rule pattern="0[xX][0-9a-fA-F]+">
+        <token type="LiteralNumberHex"/>
+      </rule>
+      <rule pattern="(0|[1-9][0-9]*)">
+        <token type="LiteralNumberInteger"/>
+      </rule>
+      <rule pattern="[a-zA-Z_]\w*">
+        <token type="Name"/>
+      </rule>
+      <rule pattern="[+%=&gt;&lt;|^!?/\-*&amp;~:]">
+        <token type="Operator"/>
+      </rule>      
+      <rule pattern="[{}()\[\],.;\|]">
+        <token type="Punctuation"/>
+      </rule>      
+    </state>
+  </rules>
+</lexer>

lexers/testdata/whiley.actual

@@ -0,0 +1,76 @@
+
+import uint from std::integer
+import uinteger from js::core
+import random from js::math
+import Document, Window, CanvasRenderingContext2D from w3c::dom
+import Element,HTMLCanvasElement, HTMLImageElement, MouseEvent from w3c::dom
+
+import model
+import view
+
+/**
+ * Add a given number of bombs to the board.
+ */
+method add_random_bombs(model::Board board, uint n) -> model::Board:
+    uinteger remaining = |board.squares|   
+    // Use Knuth's algorithm S
+    for x in 0..board.width:
+        for y in 0..board.height:
+            // Flip a coin (so-to-speak)
+            if random(remaining) < n:
+                // create bomb square
+                model::Square s = model::HiddenSquare(true,false)
+                // Update board
+                board = model::set_square(board,(uint) x, (uint) y,s)
+                // Reduce number of bombs to place
+                n = n - 1
+            // Reduce remaining options
+            remaining = remaining - 1
+    // return updated board
+    return board
+
+/**
+ * Handle a mouse event on the canvas
+ */
+method onclick_handler(MouseEvent e, &view::State state, Window window):
+    // Convert from view to world coordinates
+    uint x = e->offsetX / state->gridsize
+    uint y = e->offsetY / state->gridsize
+    // Update board
+    if e->shiftKey:
+        state->board = model::flag_square(state->board,x,y)
+    else:
+        state->board = model::expose_square(state->board,x,y)
+    // Render initial board
+    view::draw_board(*state)
+    // Finally determine game status
+    (bool gameOver, bool winner) = model::is_gameover(state->board)
+    // Check whether game over
+    if gameOver:
+        // Yes, but win or lose?
+        if winner:
+            window->alert("Well done --- You Found all the Mines!")
+        else:
+            window->alert("Game Over --- You Lost!")
+    // Done
+
+/**
+ * Create a new game of Minesweeper
+ */
+public export method main(uint width, uint height, uint bombs, Window window, HTMLCanvasElement canvas, HTMLImageElement[] images)
+// Requires at least 9 images
+requires |images| == 13:
+    Document document = window->document
+    // NOTE: following should not be required!
+    Element c = document->getElementById("myCanvas")
+    // Create a standard sized board
+    model::Board board = model::Board(width,height)
+    // Add bombs
+    board = add_random_bombs(board,bombs)
+    // Initialise the view state
+    &view::State state = new view::init(document,canvas,board,images)
+    // Render initial board
+    view::draw_board(*state)
+    // Configure mouse click listener
+    c->addEventListener("click",&(MouseEvent e -> onclick_handler(e,state,window)))
+