CompositionScanners are used to measure text and determine where line breaks and space padding should occur.

	intialize-release
	forParagraph:

	scanning
	composeFrom:inRectangle:firstLine:leftSide:rightSide: composeLine:fromCharacterIndex:inParagraph: setActualFont:

	stop conditions
	columnBreak cr crossedX endOfRun placeEmbeddedObject: setFont setStopConditions space tab

	accessing	top
	rightX Meaningful only when a line has just been composed -- refers to the line most recently composed. This is a subtrefuge to allow for easy resizing of a composition rectangle to the width of the maximum line. Useful only when there is only one line in the form or when each line is terminated by a carriage return. Handy for sizing menus and lists.

	intialize-release	top
	forParagraph: Initialize the receiver for scanning the given paragraph.

	scanning	top
	composeFrom:inRectangle:firstLine:leftSide:rightSide: Answer an instance of TextLineInterval that represents the next line in the paragraph.
	composeLine:fromCharacterIndex:inParagraph: Answer an instance of TextLineInterval that represents the next line in the paragraph.
	setActualFont: Keep track of max height and ascent for auto lineheight

	stop conditions	top
	columnBreak Answer true. Set up values for the text line interval currently being composed.
	cr Answer true. Set up values for the text line interval currently being composed.
	crossedX There is a word that has fallen across the right edge of the composition rectangle. This signals the need for wrapping which is done to the last space that was encountered, as recorded by the space stop condition.
	endOfRun Answer true if scanning has reached the end of the paragraph. Otherwise step conditions (mostly install potential new font) and answer false.
	placeEmbeddedObject: Place the anchoredMorph or return false if it cannot be placed. In any event, advance destX by its width.
	setFont Set the font and other emphasis.
	setStopConditions Set the font and the stop conditions for the current run.
	space Record left x and character index of the space character just encounted. Used for wrap-around. Answer whether the character has crossed the right edge of the composition rectangle of the paragraph.
	tab Advance destination x according to tab settings in the paragraph's textStyle. Answer whether the character has crossed the right edge of the composition rectangle of the paragraph.