Class InputTokenizer Object text pos Methods Tokenizer new super new. pos <- 0. text <- '' | input: inputString pos <- 1. text <- inputString. | next: recognizer (pos = ((text size) + 1)) ifTrue: [ ^nil. ]. recognizer setNextToken: (text at: pos). whileFalse (recognizer hasValidValue) [ pos <- (pos + 1). (pos = ((text size) + 1)) ifTrue: [ ^nil. ]. ifFalse: [recognizer setNextToken: (text at: pos)]. ] ^(recognizer value). | nextToken (pos = (text size)) ifTrue: [ ^nil. ] ifFalse: [ pos <- (pos + 1). ^(text at: pos). ]. ]