'From Squeak2.8alpha of 18 January 2000 [latest update: #1873] on 28 February 2000 at 5:49:31 pm'!
"Change Set:		numcase-bf
Date:			28 February 2000
Author:			Bert Freudenberg

Makes number reading independent of case"!


!Character methodsFor: 'accessing' stamp: 'bf 2/28/2000 17:42'!
digitValue
	"Answer 0-9 if the receiver is $0-$9, 10-35 if it is $A-$Z or $a-$z, and < 0 otherwise. This is used to parse literal numbers of radix 2-36."

	value <= $9 asciiValue 
		ifTrue: [^value - $0 asciiValue].
	(value between: $A asciiValue and: $Z asciiValue)
		ifTrue: [^value - $A asciiValue + 10].
	(value between: $a asciiValue and: $z asciiValue)
		ifTrue: [^value - $a asciiValue + 10].
	^ -1! !


!Number class methodsFor: 'instance creation' stamp: 'bf 2/28/2000 17:39'!
readRemainderOf: integerPart from: aStream base: base withSign: sign
	"Read optional fractional part and exponent, and return the final result"

	| value fraction fracpos |

	value _ integerPart.
	(aStream peekFor: $.)
		ifTrue: 
			["<integer>.<fraction>"
			(aStream atEnd not and: [aStream peek digitValue between: 0 and: base - 1])
				ifTrue: 
					[fracpos _ aStream position.
					fraction _ Integer readFrom: aStream base: base.
					fraction _ 
						fraction asFloat / (base raisedTo: aStream position - fracpos).
					value _ value asFloat + fraction]
				ifFalse: 
					["oops - just <integer>."
					aStream skip: -1.		"un-gobble the period"
					^ value * sign
					"Number readFrom: '3r-22.2'"]].
	((aStream peekFor: $e) or: [aStream peekFor: $E])
		ifTrue: 
			["<integer>e<exponent>"
			value _ value * (base raisedTo: (Integer readFrom: aStream))].
	(value isFloat and: [value = 0.0 and: [sign = -1]])
		ifTrue: [^ Float negativeZero]
		ifFalse: [^ value * sign]! !