etnms/etnms.tex
changeset 95 c969a973fcae
parent 94 2e2dca212fff
child 100 397b31867ea6
equal deleted inserted replaced
94:2e2dca212fff 95:c969a973fcae
    35 \newcommand{\ONE}{\mbox{\bf 1}}
    35 \newcommand{\ONE}{\mbox{\bf 1}}
    36 \def\bders{\textit{bders}}
    36 \def\bders{\textit{bders}}
    37 \def\lexer{\mathit{lexer}}
    37 \def\lexer{\mathit{lexer}}
    38 \def\blexer{\textit{blexer}}
    38 \def\blexer{\textit{blexer}}
    39 \def\blexers{\mathit{blexer\_simp}}
    39 \def\blexers{\mathit{blexer\_simp}}
       
    40 \def\simp{\mathit{simp}}
    40 \def\mkeps{\mathit{mkeps}}
    41 \def\mkeps{\mathit{mkeps}}
    41 \def\bmkeps{\textit{bmkeps}}
    42 \def\bmkeps{\textit{bmkeps}}
    42 \def\inj{\mathit{inj}}
    43 \def\inj{\mathit{inj}}
    43 \def\Empty{\mathit{Empty}}
    44 \def\Empty{\mathit{Empty}}
    44 \def\Left{\mathit{Left}}
    45 \def\Left{\mathit{Left}}
   248 for example,
   249 for example,
   249 $\retrieve \; \AALTS(Z, \AONE(S), \AONE(S)) \; \Left(\Empty)$
   250 $\retrieve \; \AALTS(Z, \AONE(S), \AONE(S)) \; \Left(\Empty)$
   250 is defined, but not $\retrieve \; \AONE(\Z\S) \; \Left(\Empty)$,
   251 is defined, but not $\retrieve \; \AONE(\Z\S) \; \Left(\Empty)$,
   251 though we can extract the same POSIX
   252 though we can extract the same POSIX
   252 bits from the two annotated regular expressions.
   253 bits from the two annotated regular expressions.
       
   254 The latter might occur when we try to retrieve from 
       
   255 a simplified regular expression using the same value
       
   256 as the unsimplified one.
       
   257 This is because $\Left(\Empty)$ corresponds to
       
   258 the regular expression structure $\AALTS$ instead of
       
   259 $\AONE$, this v
   253 That means, if we 
   260 That means, if we 
   254 want to prove that 
   261 want to prove that 
   255 \begin{center}
   262 \begin{center}
   256 $\textit{decode} \; \bmkeps \; \rup\backslash s \; r = \textit{decode} \; \bmkeps \; \rup\backslash_{simp} s \; r$
   263 $\textit{decode} \; \bmkeps \; \rup\backslash s \; r = \textit{decode} \; \bmkeps \; \rup\backslash_{simp} s \; r$
   257 \end{center}
   264 \end{center}
   263 $\retrieve \; \rup\backslash_{simp} s \; \mkeps(r\backslash s)=\textit{retrieve} \; \rup\backslash s \; \mkeps(r\backslash s)$
   270 $\retrieve \; \rup\backslash_{simp} s \; \mkeps(r\backslash s)=\textit{retrieve} \; \rup\backslash s \; \mkeps(r\backslash s)$
   264 \end{center}
   271 \end{center}
   265 \noindent
   272 \noindent
   266 we would need to rectify the value $\mkeps(r\backslash s)$ into something simpler
   273 we would need to rectify the value $\mkeps(r\backslash s)$ into something simpler
   267 to make the retrieve function defined.\\
   274 to make the retrieve function defined.\\
       
   275 One way to do this is to prove the following:
       
   276 \begin{center}
       
   277 $\retrieve \; \rup\backslash_{simp} s \; \mkeps(\simp(r\backslash s))=\textit{retrieve} \; \rup\backslash s \; \mkeps(r\backslash s)$
       
   278 \end{center}
       
   279 \noindent
   268 %HERE CONSTRUCTION SITE
   280 %HERE CONSTRUCTION SITE
   269 The vsimp function, defined as follows
   281 The vsimp function, defined as follows
   270 tries to simplify the value in lockstep with 
   282 tries to simplify the value in lockstep with 
   271 regular expression:\\
   283 regular expression:\\
   272 
   284