Applesoft tokenization phases?

Hello,


This question relates to thread "Languages with Optional Spaces".


In an Applesoft II manual I've found at "classiccmp.org" [1], page 7,
we read that in a variable name any alphanumeric characters after the
first two are ignored, unless they contain a reserved world. FEND ie
would be illegal as it contains END.


To implement such a rule one could first recognize keywords and then
recognize any names. We see in p123 that stmt I is tokenized as II:
    I. stmt: 100 FOR A = LOFT OR CAT To 15
II. tokens: 100 FOR A = LOF TO RC AT To 15


Yet, I've found ie a program at "hoist-point.com" [2] that contains:
110 DIFF = ABS(A(I)-N)


Also, an online AppleSoft simulator at calormen.com [3] accepts ie both
DIFF and FEND as valid variable names.


As it seems, this issue can affect a design choice for the tokenization
phases of an Applesoft front-end. Is the manual just informative or the
online simulator does not accept (precisely) the particular dialect?




Ev. Drikos




PS: The eight (8) Basic examples in the Compukit UK101 Simulator project
seem to be compatible to Applesoft, although I haven't seen this term in
the site [4] or the computer manual that contains a Basic Reference; not
sure also if the Superboard II accepts a dialect compatible to Applesoft.


------------------------------------------------------------------------
[1] http://www.classiccmp.org/cini/pdf/Apple/
[2] http://www.hoist-point.com/applesoft_basic_tutorial.htm
[3] https://www.calormen.com/jsbasic/
[4] http://uk101.sourceforge.net/docs/index.html

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