607 lines
13 KiB
Plaintext
607 lines
13 KiB
Plaintext
# Rules providing basic arithmetic operations
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HAIKU_ZERO = + 0 ;
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HAIKU_ONE = + 1 ;
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HAIKU_PAD_9 = 0 1 2 3 4 5 6 7 8 ;
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# a > b <==> $(HAIKU_DIGIT_GREATER_$(a)[1$(b)])
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HAIKU_DIGIT_GREATER_0 = $(HAIKU_PAD_9) ;
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HAIKU_DIGIT_GREATER_1 = $(HAIKU_PAD_9) 1 ;
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HAIKU_DIGIT_GREATER_2 = $(HAIKU_PAD_9) 1 1 ;
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HAIKU_DIGIT_GREATER_3 = $(HAIKU_PAD_9) 1 1 1 ;
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HAIKU_DIGIT_GREATER_4 = $(HAIKU_PAD_9) 1 1 1 1 ;
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HAIKU_DIGIT_GREATER_5 = $(HAIKU_PAD_9) 1 1 1 1 1 ;
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HAIKU_DIGIT_GREATER_6 = $(HAIKU_PAD_9) 1 1 1 1 1 1 ;
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HAIKU_DIGIT_GREATER_7 = $(HAIKU_PAD_9) 1 1 1 1 1 1 1 ;
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HAIKU_DIGIT_GREATER_8 = $(HAIKU_PAD_9) 1 1 1 1 1 1 1 1 ;
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HAIKU_DIGIT_GREATER_9 = $(HAIKU_PAD_9) 1 1 1 1 1 1 1 1 1 ;
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# a + b == $(HAIKU_DIGIT_ADD_$(a)[1$(b)]) (carry ignored)
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HAIKU_DIGIT_ADD_0 = $(HAIKU_PAD_9) 0 1 2 3 4 5 6 7 8 9 ;
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HAIKU_DIGIT_ADD_1 = $(HAIKU_PAD_9) 1 2 3 4 5 6 7 8 9 0 ;
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HAIKU_DIGIT_ADD_2 = $(HAIKU_PAD_9) 2 3 4 5 6 7 8 9 0 1 ;
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HAIKU_DIGIT_ADD_3 = $(HAIKU_PAD_9) 3 4 5 6 7 8 9 0 1 2 ;
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HAIKU_DIGIT_ADD_4 = $(HAIKU_PAD_9) 4 5 6 7 8 9 0 1 2 3 ;
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HAIKU_DIGIT_ADD_5 = $(HAIKU_PAD_9) 5 6 7 8 9 0 1 2 3 4 ;
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HAIKU_DIGIT_ADD_6 = $(HAIKU_PAD_9) 6 7 8 9 0 1 2 3 4 5 ;
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HAIKU_DIGIT_ADD_7 = $(HAIKU_PAD_9) 7 8 9 0 1 2 3 4 5 6 ;
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HAIKU_DIGIT_ADD_8 = $(HAIKU_PAD_9) 8 9 0 1 2 3 4 5 6 7 ;
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HAIKU_DIGIT_ADD_9 = $(HAIKU_PAD_9) 9 0 1 2 3 4 5 6 7 8 ;
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# a - b == $(HAIKU_DIGIT_SUB_$(a)[1$(b)]) (carry ignored)
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HAIKU_DIGIT_SUB_0 = $(HAIKU_PAD_9) 0 9 8 7 6 5 4 3 2 1 ;
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HAIKU_DIGIT_SUB_1 = $(HAIKU_PAD_9) 1 0 9 8 7 6 5 4 3 2 ;
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HAIKU_DIGIT_SUB_2 = $(HAIKU_PAD_9) 2 1 0 9 8 7 6 5 4 3 ;
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HAIKU_DIGIT_SUB_3 = $(HAIKU_PAD_9) 3 2 1 0 9 8 7 6 5 4 ;
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HAIKU_DIGIT_SUB_4 = $(HAIKU_PAD_9) 4 3 2 1 0 9 8 7 6 5 ;
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HAIKU_DIGIT_SUB_5 = $(HAIKU_PAD_9) 5 4 3 2 1 0 9 8 7 6 ;
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HAIKU_DIGIT_SUB_6 = $(HAIKU_PAD_9) 6 5 4 3 2 1 0 9 8 7 ;
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HAIKU_DIGIT_SUB_7 = $(HAIKU_PAD_9) 7 6 5 4 3 2 1 0 9 8 ;
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HAIKU_DIGIT_SUB_8 = $(HAIKU_PAD_9) 8 7 6 5 4 3 2 1 0 9 ;
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HAIKU_DIGIT_SUB_9 = $(HAIKU_PAD_9) 9 8 7 6 5 4 3 2 1 0 ;
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# a * b == $(HAIKU_DIGIT_MULT_CARRY_$(a)[1$(b)]) $(HAIKU_DIGIT_MULT_$(a)[1$(b)])
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HAIKU_DIGIT_MULT_0 = $(HAIKU_PAD_9) 0 0 0 0 0 0 0 0 0 0 ;
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HAIKU_DIGIT_MULT_1 = $(HAIKU_PAD_9) 0 1 2 3 4 5 6 7 8 9 ;
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HAIKU_DIGIT_MULT_2 = $(HAIKU_PAD_9) 0 2 4 6 8 0 2 4 6 8 ;
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HAIKU_DIGIT_MULT_3 = $(HAIKU_PAD_9) 0 3 6 9 2 5 8 1 4 7 ;
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HAIKU_DIGIT_MULT_4 = $(HAIKU_PAD_9) 0 4 8 2 6 0 4 8 2 6 ;
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HAIKU_DIGIT_MULT_5 = $(HAIKU_PAD_9) 0 5 0 5 0 5 0 5 0 5 ;
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HAIKU_DIGIT_MULT_6 = $(HAIKU_PAD_9) 0 6 2 8 4 0 6 2 8 4 ;
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HAIKU_DIGIT_MULT_7 = $(HAIKU_PAD_9) 0 7 4 1 8 5 2 9 6 3 ;
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HAIKU_DIGIT_MULT_8 = $(HAIKU_PAD_9) 0 8 6 4 2 0 8 6 4 2 ;
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HAIKU_DIGIT_MULT_9 = $(HAIKU_PAD_9) 0 9 8 7 6 5 4 3 2 1 ;
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HAIKU_DIGIT_MULT_CARRY_0 = $(HAIKU_PAD_9) 0 0 0 0 0 0 0 0 0 0 ;
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HAIKU_DIGIT_MULT_CARRY_1 = $(HAIKU_PAD_9) 0 0 0 0 0 0 0 0 0 0 ;
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HAIKU_DIGIT_MULT_CARRY_2 = $(HAIKU_PAD_9) 0 0 0 0 0 1 1 1 1 1 ;
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HAIKU_DIGIT_MULT_CARRY_3 = $(HAIKU_PAD_9) 0 0 0 0 1 1 1 2 2 2 ;
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HAIKU_DIGIT_MULT_CARRY_4 = $(HAIKU_PAD_9) 0 0 0 1 1 2 2 2 3 3 ;
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HAIKU_DIGIT_MULT_CARRY_5 = $(HAIKU_PAD_9) 0 0 1 1 2 2 3 3 4 4 ;
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HAIKU_DIGIT_MULT_CARRY_6 = $(HAIKU_PAD_9) 0 0 1 1 2 3 3 4 4 5 ;
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HAIKU_DIGIT_MULT_CARRY_7 = $(HAIKU_PAD_9) 0 0 1 2 2 3 4 4 5 6 ;
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HAIKU_DIGIT_MULT_CARRY_8 = $(HAIKU_PAD_9) 0 0 1 2 3 4 4 5 6 7 ;
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HAIKU_DIGIT_MULT_CARRY_9 = $(HAIKU_PAD_9) 0 0 1 2 3 4 5 6 7 8 ;
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# pragma mark - Number Operations
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rule NormalizeNum number
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{
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# NormalizeNum <number> ;
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local sign ;
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if $(number[1]) = "-" || $(number[1] = "+" {
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sign = $(number[1]) ;
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number = $(number[2-]) ;
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} else {
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sign = "+" ;
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}
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# cut off leading zeros
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local number = [ FReverse $(number) ] ;
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while $(number[1]) = 0 {
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number = $(number[2-]) ;
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}
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number = [ FReverse $(number) ] ;
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# zero is respresented as + 0
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if ! $(number) {
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number = 0 ;
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sign = "+" ;
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}
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return $(sign) $(number) ;
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}
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rule Num string : dontExit
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{
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# Num <number string> [ : <dontExit> ] ;
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# split the string into three parts: sign, digits, and remainder
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local temp = [ Match ([^0-9]*)([0-9]+)(.*) : $(string) ] ;
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# there must be digits, but there must not be a remainder
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if ! $(temp[2]) || $(temp[3]) {
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if $(dontExit) {
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return ;
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}
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Exit "Not a number" ;
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}
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# get the sign
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local number ;
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if ! $(temp[1]) {
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number = "+" ;
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} else if $(temp[1]) = "+" || $(temp[1]) = "-" {
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number = $(temp[1]) ;
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} else {
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if $(dontExit) {
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return ;
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}
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Exit "Not a number (sign)" ;
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}
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# split the digits
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temp = $(temp[2]) ;
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while $(temp[1]) {
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# split off the last digit
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temp = [ Match (.*)([0-9]) : $(temp[1]) ] ;
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number += $(temp[2]) ;
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}
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# normalize
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return [ NormalizeNum $(number) ] ;
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}
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rule Num2String number
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{
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# Num2String <number> ;
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local sign = $(number[1]) ;
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if $(sign) = "+" {
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sign = "" ;
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}
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number = [ FReverse $(number[2-]) ] ;
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return $(sign)$(number:J=) ;
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}
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rule NumGreaterAbs a : b
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{
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# NumGreaterAbs <a> : <b> ;
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# we compare from least to most significant digit
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local cmp = 0 ;
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while $(a) && $(b) {
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# chop off the first digit
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local da = $(a[1]:E=0) ;
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local db = $(b[1]:E=0) ;
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a = $(a[2-]) ;
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b = $(b[2-]) ;
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if $(da) != $(db) {
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if $(HAIKU_DIGIT_GREATER_$(da)[1$(db)]) {
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cmp = 1 ;
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} else {
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cmp = -1 ;
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}
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}
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}
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# a is greater, if b is not longer and a is either longer or equally long
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# and greater according to the digits comparison
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if ! $(b) && ( $(a) || $(cmp) = 1 ) {
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return 1 ;
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}
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return ;
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}
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rule AddNumAbs a : b
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{
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# AddNum <a> : <b> ;
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local result ;
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local carry ;
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while $(a) || $(b) || $(carry) {
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# chop off the first digit
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local da = $(a[1]:E=0) ;
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local db = $(b[1]:E=0) ;
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a = $(a[2-]) ;
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b = $(b[2-]) ;
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# add carry to the first digit
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if $(carry) {
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local daa = $(HAIKU_DIGIT_ADD_1[1$(da)]) ;
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carry = $(HAIKU_DIGIT_GREATER_$(da)[1$(daa)]) ;
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da = $(daa) ;
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}
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# add digits
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local dr = $(HAIKU_DIGIT_ADD_$(da)[1$(db)]) ;
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if $(HAIKU_DIGIT_GREATER_$(da)[1$(dr)]) {
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carry = 1 ;
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}
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result += $(dr) ;
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}
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return $(result) ;
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}
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rule SubNumAbs a : b
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{
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# SubNum <a> : <b> ;
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local result ;
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local carry ;
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while $(a) && ( $(b) || $(carry) ) {
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# chop off the first digit
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local da = $(a[1]:E=0) ;
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local db = $(b[1]:E=0) ;
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a = $(a[2-]) ;
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b = $(b[2-]) ;
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# sub carry from the first digit
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if $(carry) {
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local daa = $(HAIKU_DIGIT_SUB_$(da)[11]) ;
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carry = $(HAIKU_DIGIT_GREATER_$(daa)[1$(da)]) ;
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da = $(daa) ;
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}
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# sub digits
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local dr = $(HAIKU_DIGIT_SUB_$(da)[1$(db)]) ;
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if $(HAIKU_DIGIT_GREATER_$(dr)[1$(da)]) {
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carry = 1 ;
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}
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result += $(dr) ;
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}
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if $(b) || $(carry) {
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Exit "Error: SubNumAbs: Can't subtract greater from smaller number." ;
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}
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return $(result) ;
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}
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rule NegNum a
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{
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# NegNum <a> ;
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if $(a[1]) = "+" {
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if $(a) = $(HAIKU_ZERO) {
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return $(a) ;
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}
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return "-" $(a[2-]) ;
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} else {
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return "+" $(a[2-]) ;
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}
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}
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rule AddNum a : b
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{
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# AddNum <a> : <b> ;
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local signa = $(a[1]) ;
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local signb = $(b[1]) ;
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a = $(a[2-]) ;
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b = $(b[2-]) ;
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if $(signa) = $(signb) {
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return $(signa) [ AddNumAbs $(a) : $(b) ] ;
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} else {
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local result ;
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if [ NumGreaterAbs $(a) : $(b) ] {
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result = $(signa) [ SubNumAbs $(a) : $(b) ] ;
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} else {
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result = $(signb) [ SubNumAbs $(b) : $(a) ] ;
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}
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return [ NormalizeNum $(result) ] ;
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}
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}
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rule SubNum a : b
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{
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# SubNum <a> : <b> ;
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return [ AddNum $(a) : [ NegNum $(b) ] ] ;
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}
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rule MultNumAbsDigit a : digit
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{
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# MultNumAbsDigit <a> : <digit> ;
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local digitMultiples = $(HAIKU_DIGIT_MULT_$(digit)) ;
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local digitCarries = $(HAIKU_DIGIT_MULT_CARRY_$(digit)) ;
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local result ;
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local carry = 0 ;
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while $(a) || $(carry) != 0 {
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# chop off the first digit
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local da = $(a[1]:E=0) ;
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a = $(a[2-]) ;
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local dr = $(digitMultiples[1$(da)]) ;
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# add carry to the resulting digit
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if $(carry) {
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local dra = $(HAIKU_DIGIT_ADD_$(dr)[1$(carry)]) ;
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carry = $(HAIKU_DIGIT_GREATER_$(dr)[1$(dra)]:E=0) ;
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dr = $(dra) ;
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}
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# new carry
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carry = $(HAIKU_DIGIT_ADD_$(carry:E=0)[1$(digitCarries[1$(da)])]) ;
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result += $(dr) ;
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}
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return $(result) ;
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}
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rule MultNum a : b
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{
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# MultNum <a> : <b> ;
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# If one of the factors is 0, we save us computation and normalization.
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if $(a) = $(HAIKU_ZERO) || $(b) = $(HAIKU_ZERO) {
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return $(HAIKU_ZERO) ;
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}
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# get the sign for the result
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local sign = "+" ;
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if $(a[1]) != $(b[1]) {
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sign = "-" ;
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}
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a = $(a[2-]) ;
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b = $(b[2-]) ;
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# multiply the individual digits of b with a and add up the result
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local result = 0 ;
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local prefix ;
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while $(b) {
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local db = $(b[1]) ;
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b = $(b[2-]) ;
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local adb = $(prefix) [ MultNumAbsDigit $(a) : $(db) ] ;
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result = [ AddNumAbs $(result) : $(adb) ] ;
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prefix += 0 ;
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}
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return $(sign) $(result) ;
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}
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rule NumGreater a : b
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{
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local signa = $(a[1]) ;
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local signb = $(b[1]) ;
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a = $(a[2-]) ;
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b = $(b[2-]) ;
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if $(signa) = $(signb) {
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if $(signa) = "+" {
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return [ NumGreaterAbs $(a) : $(b) ] ;
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} else {
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return [ NumGreaterAbs $(b) : $(a) ] ;
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}
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} else {
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if $(signa) = "+" {
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return 1 ;
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} else {
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return ;
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}
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}
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}
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# pragma mark - Number String Operations
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rule Inc a
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{
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# Inc <number string a> ;
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return [ Num2String [ AddNum [ Num $(a) ] : + 1 ] ] ;
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}
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rule Dec a
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{
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# Dec <number string a> ;
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return [ Num2String [ AddNum [ Num $(a) ] : - 1 ] ] ;
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}
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rule Neg a
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{
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# Neg <number string a> ;
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return [ Num2String [ NegNum [ Num $(a) ] ] ] ;
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}
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rule Add a : b
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{
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# Add <number string a> : <number string b> ;
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return [ Num2String [ AddNum [ Num $(a) ] : [ Num $(b) ] ] ] ;
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}
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rule Sub a : b
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{
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# Sub <number string a> : <number string b> ;
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return [ Num2String [ SubNum [ Num $(a) ] : [ Num $(b) ] ] ] ;
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}
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rule Mult a : b
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{
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# Mult <number string a> : <number string b> ;
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return [ Num2String [ MultNum [ Num $(a) ] : [ Num $(b) ] ] ] ;
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}
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rule Equal a : b
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{
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# Equal <number string a> : <number string b> ;
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if [ Num $(a) ] = [ Num $(b) ] {
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return 1 ;
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}
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return ;
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}
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rule Less a : b
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{
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# Less <number string a> : <number string b> ;
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return [ NumGreater [ Num $(b) ] : [ Num $(a) ] ] ;
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}
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rule Greater a : b
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{
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# Greater <number string a> : <number string b> ;
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return [ NumGreater [ Num $(a) ] : [ Num $(b) ] ] ;
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}
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rule LessOrEqual a : b
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{
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# LessOrEqual <number string a> : <number string b> ;
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if [ NumGreater [ Num $(a) ] : [ Num $(b) ] ] {
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return ;
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}
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return 1 ;
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}
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rule GreaterOrEqual a : b
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{
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# GreaterOrEqual <number string a> : <number string b> ;
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if [ NumGreater [ Num $(b) ] : [ Num $(a) ] ] {
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return ;
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}
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return 1 ;
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}
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# pragma mark - Expression Parser
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rule ParseAtom expression
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{
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# ParseAtom <expression> ;
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# expression: '(' expression ')' | number
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if $(expression[1]) = "(" {
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local result = [ ParseExpression $(expression[2-]) ] ;
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if $(result[2]) != ")" {
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Exit "ParseAtom: Parse error: Expected \")\"." ;
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}
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return $(result[1]) $(result[3-]) ;
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} else {
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if ! $(expression) {
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Exit "ParseAtom: Parse error: Unexpected end of expression." ;
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}
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local num = [ Num $(expression[1]) : 1 ] ;
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if ! $(num) {
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Exit "ParseAtom: Parse error: Expected number instead of:"
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$(expression[1]) ;
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}
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return [ Num2String $(num) ] $(expression[2-]) ;
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}
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}
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rule ParseUnary expression
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{
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# ParseUnary <expression> ;
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# expression: ('+'/'-')* atom
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if ! $(expression) {
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Exit "ParseUnary: Parse error: Unexpected end of expression." ;
|
|
}
|
|
|
|
# eat all unary "+" and "-" operations
|
|
local neg ;
|
|
while $(expression[1]) = "+" || $(expression[1]) = "-" {
|
|
if $(expression[1]) = "-" {
|
|
if $(neg) {
|
|
neg = ;
|
|
} else {
|
|
neg = 1 ;
|
|
}
|
|
}
|
|
|
|
expression = $(expression[2-]) ;
|
|
}
|
|
|
|
local result = [ ParseAtom $(expression) ] ;
|
|
|
|
if $(neg) {
|
|
return [ Neg $(result[1]) ] $(result[2-]) ;
|
|
}
|
|
return $(result) ;
|
|
}
|
|
|
|
rule ParseTerm expression
|
|
{
|
|
# ParseTerm <expression> ;
|
|
|
|
# expression: unary ('*' unary)*
|
|
|
|
local result = [ ParseUnary $(expression) ] ;
|
|
local product = $(result[1]) ;
|
|
expression = $(result[2-]) ;
|
|
|
|
while $(expression[1]) = "*" {
|
|
# get the operation
|
|
local operation ;
|
|
operation = Mult ;
|
|
|
|
# parse the next operand
|
|
result = [ ParseUnary $(expression[2-]) ] ;
|
|
expression = $(result[2-]) ;
|
|
|
|
# compute the product
|
|
product = [ $(operation) $(product) : $(result[1]) ] ;
|
|
}
|
|
|
|
return $(product) $(expression) ;
|
|
}
|
|
|
|
rule ParseExpression expression
|
|
{
|
|
# ParseExpression <expression> ;
|
|
|
|
# expression: term ('+'/'-' term)*
|
|
|
|
local result = [ ParseTerm $(expression) ] ;
|
|
local sum = $(result[1]) ;
|
|
expression = $(result[2-]) ;
|
|
|
|
while $(expression[1]) = "+" || $(expression[1]) = "-" {
|
|
# get the operation
|
|
local operation ;
|
|
if $(expression[1]) = "+" {
|
|
operation = Add ;
|
|
} else {
|
|
operation = Sub ;
|
|
}
|
|
|
|
# parse the next operand
|
|
result = [ ParseTerm $(expression[2-]) ] ;
|
|
expression = $(result[2-]) ;
|
|
|
|
# compute the sum
|
|
sum = [ $(operation) $(sum) : $(result[1]) ] ;
|
|
}
|
|
|
|
return $(sum) $(expression) ;
|
|
}
|
|
|
|
|
|
rule Expr expression
|
|
{
|
|
# Expr <expression> ;
|
|
|
|
# tokenize the expression
|
|
local tokens ;
|
|
local string ;
|
|
for string in $(expression) {
|
|
while $(string) {
|
|
local split = [ Match "[ \t]*(-|[()+*]|[0-9]*)(.*)" : $(string) ] ;
|
|
if ! $(split[1]) {
|
|
Exit "Expr: Syntax error: Invalid token: \"$(string)\"." ;
|
|
}
|
|
|
|
tokens += $(split[1]) ;
|
|
string = $(split[2]) ;
|
|
}
|
|
}
|
|
|
|
local result = [ ParseExpression $(tokens) ] ;
|
|
if $(result[2-]) {
|
|
Exit "Expr: Garbage at end of expression:" $(result[2-]) ;
|
|
}
|
|
|
|
return $(result[1]) ;
|
|
}
|