RosettaCodeData/Task/Range-extraction/SNOBOL4/range-extraction.sno

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* # Absolute value
define('abs(n)') :(abs_end)
abs abs = ~(abs = lt(n,0) -n) n :(return)
abs_end
define('rangext(str)d1,d2') :(rangext_end)
rangext num = ('+' | '-' | '') span('0123456789')
rxt1 str ',' span(' ') = ' ' :s(rxt1)
rxt2 str num . d1 ' ' num . d2 =
+ d1 ('~,' ? *eq(abs(d2 - d1),1) '~' | ',') d2 :s(rxt2)
rxt3 str ('~' | '-') num '~' = '-' :s(rxt3)
rxt4 str '~' = ',' :s(rxt4)
rangext = str :(return)
rangext_end
* # Test and display
test = '0, 1, 2, 4, 6, 7, 8, 11, 12, 14, '
+ '15, 16, 17, 18, 19, 20, 21, 22, 23, 24, '
+ '25, 27, 28, 29, 30, 31, 32, 33, 35, 36, '
+ '37, 38, 39'
output = rangext(test)
end