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<P><FONT SIZE="5">1.1 Notation</FONT><BR>
<P>A particular variant of EBNF
(Extended Bachus Naur Form) will be used to
describe the FunnelWeb syntax. In this variant, literal strings are
delimited by double quotes (e.g. <SAMP>"string"</SAMP>), optional constructs by
square brackets (e.g. <SAMP>[optional]</SAMP>), and constructs repeated zero or
more times by braces (e.g. <SAMP>{zeroormore}</SAMP>). Constructs to be repeated
a fixed number of times are enclosed in braces followed by a decimal
number indicating the number of times to be repeated
(e.g. <SAMP>{sixtimes}6</SAMP>). Constructs to be
repeated one or more times are
enclosed in braces and followed by a <SAMP>+</SAMP> (e.g. <SAMP>{oneormore}+</SAMP>).
The traditional BNF "<TT>::=</TT>"
is replaced by the visually simpler "<TT>=</TT>". The traditional BNF angle
brackets are abandoned.
<P>Although FunnelWeb allows the special character to be changed using the
construct "<special>=", use of "<special>" to refer to
FunnelWeb's special character is cumbersome and abstract. To simplify
the presentation, the default special character "<TT>@</TT>" is used throughout
this chapter to represent the special character.
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