dist/picturefill.js
function tokenize() {

			// 8.1. Descriptor tokeniser: Skip whitespace
			collectCharacters(regexLeadingSpaces);

			// 8.2. Let current descriptor be the empty string.
			currentDescriptor = "";

			// 8.3. Let state be in descriptor.
			state = "in descriptor";

			while (true) {

				// 8.4. Let c be the character at position.
				c = input.charAt(pos);

				//  Do the following depending on the value of state.
				//  For the purpose of this step, "EOF" is a special character representing
				//  that position is past the end of input.

				// In descriptor
				if (state === "in descriptor") {
					// Do the following, depending on the value of c:

				  // Space character
				  // If current descriptor is not empty, append current descriptor to
				  // descriptors and let current descriptor be the empty string.
				  // Set state to after descriptor.
					if (isSpace(c)) {
						if (currentDescriptor) {
							descriptors.push(currentDescriptor);
							currentDescriptor = "";
							state = "after descriptor";
						}

					// U+002C COMMA (,)
					// Advance position to the next character in input. If current descriptor
					// is not empty, append current descriptor to descriptors. Jump to the step
					// labeled descriptor parser.
					} else if (c === ",") {
						pos += 1;
						if (currentDescriptor) {
							descriptors.push(currentDescriptor);
						}
						parseDescriptors();
						return;

					// U+0028 LEFT PARENTHESIS (()
					// Append c to current descriptor. Set state to in parens.
					} else if (c === "\u0028") {
						currentDescriptor = currentDescriptor + c;
						state = "in parens";

					// EOF
					// If current descriptor is not empty, append current descriptor to
					// descriptors. Jump to the step labeled descriptor parser.
					} else if (c === "") {
						if (currentDescriptor) {
							descriptors.push(currentDescriptor);
						}
						parseDescriptors();
						return;

					// Anything else
					// Append c to current descriptor.
					} else {
						currentDescriptor = currentDescriptor + c;
					}
				// (end "in descriptor"

				// In parens
				} else if (state === "in parens") {

					// U+0029 RIGHT PARENTHESIS ())
					// Append c to current descriptor. Set state to in descriptor.
					if (c === ")") {
						currentDescriptor = currentDescriptor + c;
						state = "in descriptor";

					// EOF
					// Append current descriptor to descriptors. Jump to the step labeled
					// descriptor parser.
					} else if (c === "") {
						descriptors.push(currentDescriptor);
						parseDescriptors();
						return;

					// Anything else
					// Append c to current descriptor.
					} else {
						currentDescriptor = currentDescriptor + c;
					}

				// After descriptor
				} else if (state === "after descriptor") {

					// Do the following, depending on the value of c:
					// Space character: Stay in this state.
					if (isSpace(c)) {

					// EOF: Jump to the step labeled descriptor parser.
					} else if (c === "") {
						parseDescriptors();
						return;

					// Anything else
					// Set state to in descriptor. Set position to the previous character in input.
					} else {
						state = "in descriptor";
						pos -= 1;

					}
				}

				// Advance position to the next character in input.
				pos += 1;

			// Repeat this step.
			} // (close while true loop)
		}
function tokenize() {

			// 8.1. Descriptor tokeniser: Skip whitespace
			collectCharacters(regexLeadingSpaces);

			// 8.2. Let current descriptor be the empty string.
			currentDescriptor = "";

			// 8.3. Let state be in descriptor.
			state = "in descriptor";

			while (true) {

				// 8.4. Let c be the character at position.
				c = input.charAt(pos);

				//  Do the following depending on the value of state.
				//  For the purpose of this step, "EOF" is a special character representing
				//  that position is past the end of input.

				// In descriptor
				if (state === "in descriptor") {
					// Do the following, depending on the value of c:

				  // Space character
				  // If current descriptor is not empty, append current descriptor to
				  // descriptors and let current descriptor be the empty string.
				  // Set state to after descriptor.
					if (isSpace(c)) {
						if (currentDescriptor) {
							descriptors.push(currentDescriptor);
							currentDescriptor = "";
							state = "after descriptor";
						}

					// U+002C COMMA (,)
					// Advance position to the next character in input. If current descriptor
					// is not empty, append current descriptor to descriptors. Jump to the step
					// labeled descriptor parser.
					} else if (c === ",") {
						pos += 1;
						if (currentDescriptor) {
							descriptors.push(currentDescriptor);
						}
						parseDescriptors();
						return;

					// U+0028 LEFT PARENTHESIS (()
					// Append c to current descriptor. Set state to in parens.
					} else if (c === "\u0028") {
						currentDescriptor = currentDescriptor + c;
						state = "in parens";

					// EOF
					// If current descriptor is not empty, append current descriptor to
					// descriptors. Jump to the step labeled descriptor parser.
					} else if (c === "") {
						if (currentDescriptor) {
							descriptors.push(currentDescriptor);
						}
						parseDescriptors();
						return;

					// Anything else
					// Append c to current descriptor.
					} else {
						currentDescriptor = currentDescriptor + c;
					}
				// (end "in descriptor"

				// In parens
				} else if (state === "in parens") {

					// U+0029 RIGHT PARENTHESIS ())
					// Append c to current descriptor. Set state to in descriptor.
					if (c === ")") {
						currentDescriptor = currentDescriptor + c;
						state = "in descriptor";

					// EOF
					// Append current descriptor to descriptors. Jump to the step labeled
					// descriptor parser.
					} else if (c === "") {
						descriptors.push(currentDescriptor);
						parseDescriptors();
						return;

					// Anything else
					// Append c to current descriptor.
					} else {
						currentDescriptor = currentDescriptor + c;
					}

				// After descriptor
				} else if (state === "after descriptor") {

					// Do the following, depending on the value of c:
					// Space character: Stay in this state.
					if (isSpace(c)) {

					// EOF: Jump to the step labeled descriptor parser.
					} else if (c === "") {
						parseDescriptors();
						return;

					// Anything else
					// Set state to in descriptor. Set position to the previous character in input.
					} else {
						state = "in descriptor";
						pos -= 1;

					}
				}

				// Advance position to the next character in input.
				pos += 1;

			// Repeat this step.
			} // (close while true loop)
		}
(close parseDescriptors fn) 
Tokenizes descriptor properties prior to parsing
Returns undefined.
(Again, this fn is defined before it is used, in order to pass JSHINT.
Unfortunately this breaks the logical sequencing of the spec comments. :/ )