
diff -r 24d9d64c2a95 -r f575cf219377 ninems/ninems.tex
--- a/ninems/ninems.tex	Tue Jul 16 22:18:18 2019 +0100
+++ b/ninems/ninems.tex	Tue Jul 16 22:20:11 2019 +0100
@@ -950,31 +950,25 @@
 \end{tabular}    
 \end{center}    
 %\end{definition}
-For instance, we attach an additional bit $\Z$ to
- the front of $r \backslash c$ to indicate that there
-  is one more star iteration when we unfold $\textit{STAR} \; bs \; a$ 
-into a sequence in the last clause. 
-A more subtle treatment of the bits lies in the $\textit{SEQ}$ clause
- when $a_1$ is $\textit{bnullable}$($\textit{bnullable}$
-  is exactly the same as $\textit{nullable}$, except that it is for
-   annotated regular expressions, therefore we omit the definition).
-$\textit{bmkeps} \, a_1$ extracts the bitcode accumulated in 
-$a_1$ for how the prefix $s_1$ of the input string ending at character $c$ 
-is matched by the predecessor of $a_1$(before $s_1$ was chopped off).
-Then $\textit{fuse}$ stores the information 
-extracted by $\textit{bmkeps}$ at the head of the 
-regular expression $a_2 \backslash c$. 
-The bitsequence $bs$, which was initially 
-attached to the head of $\textit{SEQ}$, has 
-now been elevated to the top-level $\textit{ALT}$,
-as this information will be needed 
-whichever way the $\textit{SEQ}\,bs \,a_1\,a_2$ is 
-matched--no matter whether $c$ belongs to $a_1$ or $ a_2$.
-After carefully doing these derivatives and 
-maintaining all the parsing information, 
-we complete the parsing by collecting the bits using 
-a special $\textit{mkeps}$ function for annotated 
-regular expressions--$\textit{bmkeps}$:
+
+For instance, when we unfold $STAR \; bs \; a$ into a sequence, we
+attach an additional bit Z to the front of $r \backslash c$ to indicate
+that there is one more star iteration. The other example, the $SEQ$
+clause is more subtle-- when $a_1$ is $bnullable$(here bnullable is
+exactly the same as nullable, except that it is for annotated regular
+expressions, therefore we omit the definition). Assume that $bmkeps$
+correctly extracts the bitcode for how $a_1$ matches the string prior to
+character c(more on this later), then the right branch of $ALTS$, which
+is $fuse \; bmkeps \;  a_1 (a_2 \backslash c)$ will collapse the regular
+expression $a_1$(as it has already been fully matched) and store the
+parsing information at the head of the regular expression $a_2
+\backslash c$ by fusing to it. The bitsequence $bs$, which was initially
+attached to the head of $SEQ$, has now been elevated to the top-level of
+ALT, as this information will be needed whichever way the $SEQ$ is
+matched--no matter whether c belongs to $a_1$ or $ a_2$. After carefully
+doing these derivatives and maintaining all the parsing information, we
+complete the parsing by collecting the bits using a special $mkeps$
+function for annotated regular expressions--$bmkeps$:
 
 
 %\begin{definition}[\textit{bmkeps}]\mbox{}
@@ -1131,21 +1125,25 @@
 \end{quote}  
 
 \noindent
-We would settle the correctness claim.
-It is relatively straightforward to establish that after one simplification step, 
-the part of a nullable derivative that corresponds to a POSIX value
-remains intact and can still be collected, 
-in other words,
+We would settle the correctness claim. It is relatively straightforward
+to establish that after one simplification step, the part of a nullable
+derivative that corresponds to a POSIX value remains intact and can
+still be collected, in other words,
+
 \begin{center}
 $\textit{bmkeps} \; r = \textit{bmkeps} \; \textit{simp} \; r\;( r\; \textit{nullable})$
 \end{center}
-as this basically comes down to proving actions like removing 
-the additional $r$ in $r+r$  does not delete important POSIX information
-in a regular expression.
-The hardcore of this problem is to prove that
+
+\noindent
+as this basically comes down to proving actions like removing the
+additional $r$ in $r+r$  does not delete important POSIX information in
+a regular expression. The hardcore of this problem is to prove that
+
 \begin{center}
 $\textit{bmkeps} \; \textit{blexer}\_{simp} \; r = \textit{bmkeps} \; \textit{blexer} \; \textit{simp} \; r$
 \end{center}
+
+\noindent
 That is, if we do derivative on regular expression r and the simplified version, 
 they can still provide the same POSIX value if there is one . 
 This is not as straightforward as the previous proposition, as the two regular expressions $r$ and $\textit{simp}\; r$




