1 \documentclass[10pt]{article}
9 \title{A MathML Editor Based on \TeX{} Syntax\\Formal Specification}
10 \author{Paolo Marinelli\\Luca Padovani\\\small\{{\tt pmarinel},{\tt lpadovan}\}{\tt @cs.unibo.it}\\\small Department of Computer Science\\\small University of Bologna}
13 \newcommand{\tmap}[1]{\llbracket#1\rrbracket}
14 \newcommand{\tadvance}{\vartriangle}
15 \newcommand{\tnext}{\rhd}
16 \newcommand{\G}{\texttt{g}}
17 \newcommand{\PNODE}{\texttt{p}}
18 \newcommand{\SNODE}{\texttt{s}}
19 \newcommand{\INODE}{\texttt{i}}
20 \newcommand{\NNODE}{\texttt{n}}
21 \newcommand{\ONODE}{\texttt{o}}
22 \newcommand{\CNODE}{\texttt{c}}
23 \newcommand{\TABLE}{\texttt{table}}
24 \newcommand{\SP}{\texttt{sp}}
25 \newcommand{\SB}{\texttt{sb}}
26 \newcommand{\CELL}{\texttt{cell}}
27 \newcommand{\ROW}{\texttt{row}}
28 \newcommand{\SLDROP}{\blacktriangleleft}
29 \newcommand{\NLDROP}{\vartriangleleft}
30 \newcommand{\RGROUP}{\vartriangleleft_{rg}}
38 The following tokens are defined:
40 \begin{tabular}{lllp{0.5\textwidth}}
41 \textbf{\TeX{}} & \textbf{Notation} & \textbf{Node} & \textbf{Description} \\
43 \verb+{+ & $\mathrm{begin}$ & \texttt{g} & Beginning of a group \\
44 \verb+}+ & $\mathrm{end}$ & & End of a group \\
45 \verb+$+ & $\$$ & \texttt{math} & Math shift \\ %$ \\
47 \verb+#+$i$ & $p(i)$ & \texttt{p} & Parameter \\
48 \verb+^+ & $\uparrow$ & \texttt{sp} & Superscript \\
49 \verb+_+ & $\downarrow$ & \texttt{sb} & Subscript \\
50 & $\square$ & & Space-like character that can be ignored \\
51 & $s$ & \texttt{s} & Space-like character that may be significant \\
52 letter & $i(v)$ & \texttt{i} & Identifier $v$ \\
53 digit & $n(v)$ & \texttt{n} & Number $v$ \\
54 other & $o(v)$ & \texttt{o} & Other character or operator $v$ \\
55 \verb+~+ & $\sim$ & & Active character \\
56 \verb+%+ & $\%$ & & Comment \\
57 control & $c(v)\langle\alpha_1,\dots,\alpha_n\rangle$ & \texttt{c} &
58 Control sequence $v$ that expects the $\alpha_1,\dots,\alpha_n$ sequence of tokens. \\
59 backspace & $\vartriangleleft$ & & \\
60 backspace & $\blacktriangleleft$ & & \\
63 %% Some tokens are mapped directly into nodes of the TML tree. The following functions shows
66 \begin{tabular}{r@{\quad$=$\quad}l}
67 $\tmap{\{}$ & \verb+g+ \\
68 $\tmap{p(i)}$ & \verb+p[@index=+$i$\verb+]+ \\
69 $\tmap{p_l(i)}$ & \verb+p[@index=+$i$\verb+][@left-open='1']+ \\
70 $\tmap{p_r(i)}$ & \verb+p[@index=+$i$\verb+][@right-open='1']+ \\
71 $\tmap{s}$ & \verb+s+ \\
72 $\tmap{\uparrow}$ & \verb+sp+ \\
73 $\tmap{\downarrow}$ & \verb+sb+ \\
74 $\tmap{i(v)}$ & \verb+i[@value=+$v$\verb+]+ \\
75 $\tmap{n(v)}$ & \verb+n[@value=+$v$\verb+]+ \\
76 $\tmap{o(v)}$ & \verb+o[@value=+$v$\verb+]+ \\
77 $\tmap{c(v)\langle\alpha_1,\dots,\alpha_n\rangle}$ & \verb+c[@name=+$v$\verb+][^+$\tmap{\alpha_1}\cdots\tmap{\alpha_n}$\verb+$]+\\
81 %% \section{Description and Semantics of the Pattern Language}
84 %% \mathit{NodeTest} & ::= & \mathtt{*} \\
85 %% & | & \mathit{ElementType} \\
86 %% & | & \mathtt{<}~\mathit{ElementTypePattern}~\mathtt{>} \\[1ex]
87 %% \mathit{ElementTypePattern} & ::= & \mathtt{*} \\
88 %% & | & \mathit{ElementType}~(\mathtt{|}~\mathit{ElementType})^* \\
89 %% & | & \mathtt{!}\mathit{ElementType}~(\mathtt{|}~\mathit{ElementType})^*\\[1ex]
90 %% \mathit{NodePattern} & ::= & \mathit{NodeTest}~\mathit{AttributeQualifier}^*\\[1ex]
91 %% \mathit{AttributeQualifier} & ::= & \mathtt{[@}\mathit{AttributeTest}\mathtt{]}\\
92 %% & | & \mathtt{[!@}\mathit{AttributeTest}\mathtt{]}\\[1ex]
93 %% \mathit{AttributeTest} & ::= & \mathit{AttributeName} \\
94 %% & | & \mathit{AttributeName}\mathtt{='}\mathit{Text}\mathtt{'}
97 \section{Insert Rules}
99 \paragraph{Begin Group:} $\{$
102 \item{\verb+table/cursor+}\\
103 create a \texttt{row} node, create a \texttt{cell} node, create a \texttt{g} node,
104 append the cursor to the \texttt{g} node, append the \texttt{g} node to the \texttt{cell} node,
105 append the \texttt{cell} node to the \texttt{row} node, append the \texttt{row} node to the
107 \item{\verb+cursor+} \\ create a \texttt{g} node, replace the cursor with the new \texttt{g} node,
108 append the cursor to the new \texttt{g} node
111 % CASE: c/g[!@id]/cursor
118 % CASE: c[@table='1']/cursor
120 % create a g node with id, replace the cursor with the fresh g and append
121 % the cursor as only child of it
123 \paragraph{End Group:} $\}$
126 \item{\verb+g[@id]/cursor+}\\
127 remove the cursor, put $\tadvance$ after the \texttt{g} node
128 \item{\verb+row/cell/g/cursor+}\\
129 remove the cursor, put $\tadvance$ after the \texttt{row} node
130 \item{\verb+math/g[!@id]/cursor+}\\
132 \item{\verb+cursor+}\\
136 \paragraph{Math Shift:} $\$$
139 \item{\verb+tex/cursor+}\\
140 create a \texttt{math} node, create a \texttt{g} node, append the \texttt{g} node
141 as child of the \texttt{math} node, append the cursor as child of the \texttt{g} node
142 \item{\verb+math[@display='1']/g[!@id][*#]/cursor+}\\
143 append the cursor as last child of the \texttt{math} node
144 \item{\verb+math/g[!@id][*#]/cursor+}\\
146 \item{\verb+math[!display='1']/g[!@id]/cursor+}\\
147 set \verb+display='1'+ in the \texttt{math} node
148 \item{\verb+math/g[!@id]+}\\
149 append the cursor after the \texttt{math} node
150 \item{\verb+math/cursor+}\\
152 \item{\verb+cursor+} \\
158 % create a math node. create a g node. append g as child of math.
159 % append the cursor as child of g
160 % CASE: math[@display='1']/g[!@id][*#]/cursor
161 % append the cursor as last child of math
162 % CASE: math/g[!@id][*#]/cursor
163 % remove the cursor. Editing is done
164 % CASE: math[!display='1']/g[!@id]/cursor
165 % set the display attribute to '1'
167 % append the cursor after math (?)
169 % remove the cursor. Editing is done
173 \paragraph{Align:} $\&$
176 \item{\verb+g[@id]/cursor+}\\
177 create a \texttt{row} node, create a \texttt{cell} node, create a \texttt{g} node,
178 append the cursor to the new \texttt{g} node, append the \texttt{cell} node to the
179 the \texttt{row} node ?
180 \item{\verb+row/cell/g/cursor+}\\
181 create the \texttt{g} node, create the \texttt{cell} node, append the cursor
182 as child of the new \texttt{g} node, append the new \texttt{g} node to the new
183 \texttt{cell} node after the old \texttt{cell} node
184 \item{\verb+cursor+}\\
189 % CASE: g[@id]/cursor
190 % create a row node. create a cell node. create a g node. append the
191 % cursor to g, append the g to cell, append the cell to row, ???
192 % CASE: row/cell/g/cursor
193 % create a g node. create a cell node. appent the cursor to g,
194 % append the g to cell, insert the new cell after the existing cell
198 \paragraph{End-of-line:}
203 \paragraph{Parameter:} $p(i)$
207 \paragraph{Superscript:} $\uparrow$
210 \item{\verb+<g|p>[^#]/cursor+}\\
211 create a \SP{} node, create a \G{} node, replace the cursor with the \SP{} node,
212 append the \G{} node as first child of the \SP{} node, append the cursor as last
213 child of the \SP{} node
214 \item{\verb+<g|p>[*#]/cursor+}\\
215 create a \SP{} node, replace \texttt{*} with the \SP{} node, append \texttt{*} to
216 the \SP{} node, append cursor to the \SP{} node
217 \item{\verb+sp[^*#$][!@over='1']/cursor+}\\ %$
218 set \verb+over='1'+ in the \SP{} node
219 \item{\verb+sp[^*#$][@over='1']/cursor+}\\ %$
221 \item{\verb+cursor+}\\
226 % create sp node. create g node, replace cursor with sp, append g to sp, append cursor to sp
228 % create sp node, replace * with sp, append * to sp, append cursor to sp
229 % CASE: sp[^*#$][!@over='1']/cursor
230 % set over='1' in sp node
231 % CASE: sp[^*#$][@over='1']/cursor
236 \paragraph{Subscript:} $\downarrow$
239 \item{\verb+<g|p>[^#]/cursor+}\\
240 create a \SB{} node, create a \G{} node, replace the cursor with the \SB{} node,
241 append the \G{} node as first child of the \SB{} node, append the cursor as last
242 child of the \SB{} node
243 \item{\verb+<g|p>[*#]/cursor+}\\
244 create a \SB{} node, replace \texttt{*} with the \SB{} node, append \texttt{*} to
245 the \SB{} node, append cursor to the \SB{} node
246 \item{\verb+sb[^*#$][!@under='1']/cursor+}\\ %$
247 set \verb+under='1'+ in the \SB{} node
248 \item{\verb+sb[^*#$][@under='1']/cursor+}\\ %$
250 \item{\verb+cursor+}\\
255 % create sb node. create g node, replace cursor with sb, append g to sb, append cursor to sb
257 % create sb node, replace * with sb, append * to sb, append cursor to sb
258 % CASE: sb[^*#$][!@under='1']/cursor
259 % set over='1' in sb node
260 % CASE: sb[^*#$][@under='1']/cursor
265 \paragraph{Ignorable space:} $\square$
267 % do_ignorable_space:
270 \paragraph{Space:} $s$
273 \item{\verb+cursor+}\\
274 create \SNODE{} node, replace cursor with the \SNODE{} node, append
275 $\tadvance$ after \SNODE{} node
279 % create s node, replace cursor with s, append \advance after s
281 \paragraph{Identifier:} $i(v)$
284 \item{\verb+cursor+}\\
285 create an \INODE{}, set \verb+value=+$v$ in the \INODE{}, replace
286 cursor with \INODE{}, append $\tadvance$ after the \INODE{} node
290 % create i node, replace cursor with i, append \advance after i
292 \paragraph{Number:} $n(v)$
295 \item{\verb+cursor+}\\
296 create an \NNODE{}, set \verb+value=+$v$ in the \NNODE{}, replace
297 cursor with \NNODE{}, append $\tadvance$ after the \NNODE{} node
301 % create n node, replace cursor with n, append \advance after n
303 \paragraph{Apostrophe:} $o({}')$
306 \item{\verb+<g/p>[(sp[*#$]/g[o[@name='prime']$])#]/cursor+}\\
307 create a \ONODE{} node, set \verb+name='prime'+ in the \ONODE{},
308 append the \ONODE{} to the innermost \G{} node
309 \item{\verb+<g|p>[(sb[^sp[^*#$]/g[o[@name='prime']]$])#]/cursor+}\\
310 create a \ONODE{} node, set \verb+name='prime'+ in the \ONODE{},
311 append the \ONODE{} to the innermost \G{} node
312 \item{\verb+<g|p>[*#]/cursor+}\\
313 create a \ONODE{} node, set \verb+name='prime'+ in the \ONODE{},
314 create a \SP{} node, create a \G{} node, replace \texttt{*} with \SP{} node,
315 append the new \G{} node to the \SP{} node, append the \ONODE{}
316 node to the new \G{} node
317 \item{\verb+<g|p>[^#]/cursor+}\\
319 \item{\verb+cursor+}\\
320 cursor is not in a group, error?
324 % CASE: g[(sp[^*#$]/g[o[@name='prime']$])#]/cursor
325 % append a new o[@name='prime'] node to the inner g node
326 % CASE: g[(sb[^sp[^*#$]/g[o[@name='prime']]$])#]/cursor
327 % append a new o[@name='prime'] node to the inner g node
329 % create sp node, create g node, replace * with sp, append * to sp, append g to sp,
330 % append a new o[@name='prime'[ node to the new g node
334 % cursor is not in a group, error?
336 \paragraph{Other:} $o(v)$
338 create an \ONODE{}, set \verb+value=+$v$ in the \ONODE{}, replace
339 cursor with \ONODE{}, append $\tadvance$ after the \ONODE{} node
342 % create o node, replace cursor with o, append \advance after o
344 \paragraph{Active:} $\sim$
349 \paragraph{Comment:} $\%$
354 \paragraph{Begin Environment:} $c(\mathtt{begin})\langle\alpha_1,\dots,\alpha_n\rangle$
356 \paragraph{End Environment:} $c(\mathtt{end})\langle\rangle$
358 \paragraph{Left Delimiter:} $c(\mathtt{left})\langle\alpha\rangle$
360 \paragraph{Right Delimiter:} $c(\mathtt{right})\langle\alpha\rangle$
362 \paragraph{Carriage-Return:} $c(\mathtt{cr})\langle\rangle$
365 \item{\verb+row/cell/g/cursor+}\\
366 create a \ROW{} node, create a \CELL{} node, create a \G{}
367 node, append the cursor to the new \G{} node, append the new \G{}
368 node to the new \CELL{} node, append the new \CELL{} node to the
369 new \ROW{} node, insert the new \ROW{} node after the old \ROW{} node
370 \item{\verb+cursor+}\\
375 % CASE: row/cell/g/cursor
376 % create row node, create cell node, create g node,
377 % append cursor to g, append g to cell, append cell to row,
378 % insert new row after old row
382 \paragraph{Macro:} $c(v)\langle\alpha_1,\dots,\alpha_n\rangle$
385 \item{\verb+<p|g>/cursor+}\\
386 create a \CNODE{} node with the children corresponding to the pattern
387 $\tmap{\alpha_1}$,\dots,$\tmap{\alpha_n}$, replace the cursor with
388 the new \CNODE{} node. put $\tnext$ as the first child of the new
391 \item{\verb+*/cursor+}\\
392 create a \CNODE{} node with the children corresponding to the pattern
393 $\tmap{\alpha_1}$,\dots,$\tmap{\alpha_n}$, replace the cursor with
394 the new \CNODE{} node, put $\tnext$ as the first child of the new
395 \CNODE{} node. If $n\ne0$ emit a warning (the macro has arguments but
396 but the context wouldn't normally allow them to be entered)
401 % create a c node with children corresponding to the pattern of the macro
402 % append \nextparam as first child of the macro
404 \section{Left Drop Rules}
406 \paragraph{Normal Left Drop:} $\NLDROP$
410 %********* rules that try to express situations completely specified (there is an effective deletion) ******
412 % in the rules below, a token is either an i node, an n node, an o node, an s node or an empty c node.
413 % an empty c node is either an undefined macro or an empty macro. These c node are handled as they actually were
414 % tokens (i, n, o, s).
415 % An important observation is: a sequence of groups with id, in which every group has one and only one child and where
416 % the last group contains the cursor, is equivalent to the cursor (Is it clear?). For example:
417 % <g id="id1"><g id="id2">...<g id="idn"><cursor/></g>...</g></g> is equivalent to:
420 \item{\verb+<g|p>[(i|n|o|s|c[ ])#]/(g[@id][^#$]/++\verb+)?cursor+}\\
421 remove the cursor (and eventually the sequence of \G{} nodes with attribute \texttt{id}) and replace the token with the $\RGROUP$.
423 \item{\verb+<g|p>[g#]/(g[@id][^#$]/++\verb+)?cursor+}\\
424 remove the cursor (and eventually the sequence of \G{} nodes with attribute \texttt{id}) and append $\NLDG$ to the \G{} node preceding the cursor
426 %% there is an optional sequence of groups with id, all of which having one and only one child. The last
427 %% child of this sequence (or the root, if the sequence is empty) is a group with id, has as first element a
428 %% token and has as second and last element an eventually empty sequence of groups with id, all of which having
429 %%one and only one child. The last element of this sequence has the cursor as its child.
430 %\item{\verb+(g[@id][^#$]/++\verb+)?g[@id][^(i|n|o|s|c[ ])#$]/(g[@id][^#$]/++\verb+)?cursor+}\\
431 %replace the whole fragment with the cursor.
433 % the cursor is a macro's child. There is an eventually empty sequence of delimiters, which precedes the
434 % cursor. Before this sequence, there is a p node. This p node has as its last child a token
435 \item{\verb+c[p[(i|n|o|s|c[ ])$]((i|n|o|s|c[ ])*)#]/cursor+}\\
436 remove the cursor and replace the token with the cursor.
438 % there is a token, which precedes the cursor. The cursor is child of either a group or a parameter.
439 % the case where the cursor is child of a group with id, there are no nodes after the cusror and there
440 % are no nodes preceding the token, is handled by the first rule.
441 % This rule is duplicated below, but that one could have a wrong syntax. This one has been tested.
442 \item{\verb+<g|p>[(i|n|o|c[ ])#]/cursor+}\\
443 remove the cursor and replace the token with the cursor.
445 % cursor's parent is a script (the cursor is not the base). The script's base is an empty group with id.
446 % The script is preceded by a token.The script's parent is group or a parameter.
447 % The case where the script's parent is a group with id and the token is the first child, while
448 % the script is the last one, is handled some rules later.
449 \item{\verb+<g|p>[(i|n|o|s|c[ ])#]/<sp|sb>[^(g[@id][ ])#$]/cursor+}\\
450 remove the script and replace the token with the cursor.
452 % As above, but: we don't care who precedes the script (we do not have to remove it); the script's base
453 % is still an empty group, but it has no id.
454 % Ad above, we have to precise that the situation where the script is the only child of a group with id
455 % is handled some rules later.
456 \item{\verb+<g|p>/<sp|sb>[^(g[!@id][ ])#$]/curosr+}\\
457 replace the script with the cursor.
459 % The cursor is the last child of a script. The script's base is token.
460 \item{\verb+<g|p>/<sp|sb>[^(i|n|o|s|c[ ])#$]/cursor+}\\
461 repalce the script with the cursor.
464 %*******************************************************************************************************
465 %************** rules handling the case in which the cursor has a preceding node ***********************
466 %*******************************************************************************************************
468 %************************* the cursor's parent is a group or a parameter *******************************
470 %we consider an empty macro as a token. An empty macro is either undefined or simply empty.
472 %rule handling the case where the cursor has a preceding token and this is the first node of a group with id
473 \item{\verb+g[@id][^(i||n||o||s||c[^$])#]/cursor+}\\
474 remove the cursor and replace the \INODE{}, \NNODE{}, \ONODE{}, \SNODE{} or \CNODE{} node with the $\NLDROP$.
475 \item{\verb+<g|p>[(i||n||o||s||c[^$])#]/cursor+}\\
476 remove the \INODE{}, \NNODE{}, \ONODE{}, \SNODE{} or \CNODE{} node.
477 %it corresponds to the drop_prev_group(false).
478 \item{\verb+<g|p>[g#]/cursor+}\\
479 remove the cursor and append the $\NLDROP$ to the \G{} node.
480 %corresponds to the drop_prev_script(false).
481 \item{\verb+<g|p>[(<sp|sb>)#]/cursor+}\\
482 remove the cursor and append the $\NLDROP$ to the \SP{} or \SB{} node.
483 %rules handling the right open macros preceding the cursor.
484 \item{\verb+<g|p>[(c[^p[@right-open='1']$])#]/cursor+}\\
485 remove the cursor and append the $\NLDROP$ to the \PNODE{} node.
486 %we don't have a macro of this kind, but we don't know the future...
487 \item{\verb+<g|p>[(c[^p[!(@right-open='1')][@left-open='1'][^$]$])#]/cursor+}\\
488 remove the cursor and replace the \CNODE node with the $\NLDROP$.
489 \item{\verb+<g|p>[(c[^p[!(@right-open='1')][@left-open='1']$])#]/cursor+}\\
490 replace the \CNODE{} node with the content of the \PNODE node and replace the cursor with the $\NLDROP$.
491 %rules handling macro with parameter(s) and preceding the cursor.
492 \item{\verb+<g|p>[c#]/cursor+}\\
493 remove the cursor and append the $\NLDROP$ to the \CNODE{} node.
494 %rule handling table with rows preceding the cursor.
495 \item{\verb+<g|p>[(table[row[cell[^g$]$]$])#]/cursor+}\\
496 remove the cursor and append the $\NLDROP$ to the \G{} node, which is child of the \CELL{} node.
497 %rule handling tables without rows preceding the cursor.
498 \item{\verb+<g|p>[table#]/cursor+}\\
499 remove the cursor and append the $\NLDROP$ to the \TABLE{} node
501 %********************************* the cursor's parent is a script ******************************
503 %rule handling the case where the script's base is an empty group with id.
504 \item{\verb+<sp|sb>[^(g[@id][^$])#$]/cursor+}\\
505 replace the \SP{} or \SB{} node with the $\NLDROP$.
506 %rule handling the case where the script's base is an empty group without id
507 \item{\verb+<sp|sb>[^(g[^$])#$]/cursor+}\\
508 replace the \SP{} or \SB{} node with the cursor.
509 %rule handling the case where the script's base is something else
510 \item{\verb+<sp|sb>[^*#$]/cursor+}\\
511 replace the \SP{} or \SB{} node with it's first child and insert the $\NLDROP$ after it.
513 %********************************* the cursor's parent is a macro ********************************
515 %rule handling the case where the preceding node is a parameter
516 \item{\verb+c[p#]/cursor+}\\
517 remove the cursor and append the $\NLDROP$ to the PNODE{} node.
518 %rule handling the case where the preceding node is a delimiter
519 \item{\verb+c[(<i|n|o|s|c>)#]/cursor+}\\
520 remove the cursor and insert the $\NLDROP$ before the \INODE{}, \NNODE{}, \ONODE{}, \SNODE{} or \CNODE{} node.
522 %*************************************************************************************************
523 %*********** rules handling the case in which the cursor has no preceding nodes ******************
524 %*************************************************************************************************
526 %rule handling the case where the cursor has something else after it
527 \item{\verb+<g|p>[#*]/cursor+}\\
530 %rules handling the case where the cursor's parent is a p node and the cursor has no nodes after it.
532 %rule handling the case where the p node is a left and right open macro's child and the first p node has no elements.
533 \item{\verb+c[^(p[@left-open='1'][^$])#$]/p[@right-open='1'][^#$]/cursor+}\\
534 replace the \CNODE{} with the $\NLDROP$.
535 %rule handling the case where the p node is a left and right open macro's child and the first p node has elements.
536 \item{\verb+c[^(p[@left-open='1']#$]/p[@right-open='1'][^#$]/cursor+}\\
537 replace the \CNODE{} with the content of the PNODE{} with attribute texttt{left-open='1'} and insert $\NLDROP$ after this.
538 %rule handling the case where the p node is right open macro's child.
539 \item{\verb+c[^#$]/p[@right-open='1'][^#$]/cursor+}\\
540 replace the \CNODE{} with the $\NLDROP$.
541 %rule handling the case where the p node is a macro's child and this macro has parameter.
542 \item{\verb+c/p[^#$]/cursor+}\\
543 remove the cursor and insert the $\NLDROP$ before the \PNODE{} node.
545 %rule handling the case where the cursor has no nodes after it and its parent is a group with id
546 \item{\verb+g[@id][^#$]/cursor+}\\
547 replace the \G{} node with the $\NLDROP$.
551 \paragraph{Special Left Drop:} $\SLDROP$
555 %*******************************************************************************************************
556 %************** rules handling the case in which the cursor has a preceding node ***********************
557 %*******************************************************************************************************
559 %************************* the cursor's parent is a group or a parameter *******************************
561 %this rule is more specific than the one below which handle the case of the cursor preceded by a c node
562 \item{\verb+<g|p>[(i||n||o||s||c[^$])#]/cursor+}\\
563 remove the \INODE{}, \NNODE{}, \ONODE{}, \SNODE{} or \CNODE{} node.
564 %it corresponds to the drop_prev_group(true).
565 \item{\verb+<g|p>[g#]/cursor+}\\
566 remove the cursor and append the it to the \G{} node.
567 %corresponds to the drop_prev_script(true).
568 \item{\verb+<g|p>[(<sp|sb>)#]/cursor+}\\
569 remove the cursor and append the $\SLDROP$ to the \SP{} or \SB{} node.
570 %rules handling the right open macros preceding the cursor.
571 \item{\verb+<g|p>[(c[^p[@right-open='1']$])#]/cursor+}\\
572 remove the cursor and append the $\SLDROP$ to the \PNODE{} node.
573 %we don't have a macro of this kind, but we don't know the future...
574 \item{\verb+<g|p>[(c[^p[!(@right-open='1')][@left-open='1'][^$]$])#]/cursor+}\\
575 remove the cursor and replace the \CNODE node with the cursor.
576 \item{\verb+<g|p>[(c[^p[!(@right-open='1')][@left-open='1']$])#]/cursor+}\\
577 replace the \CNODE{} node with the content of the \PNODE node.
578 %rule handling macro with parameter(s) and preceding the cursor.
579 \item{\verb+<g|p>[c#]/cursor+}\\
580 remove the cursor and append the $\SLDROP$ to the \CNODE{} node.
581 %rule handling table with rows preceding the cursor.
582 \item{\verb+<g|p>[(table[row[cell[^g$]$]$])#]/cursor+}\\
583 remove the cursor and append the it to the \G{} node, which is child of the \CELL{} node.
584 %rule handling tables without rows preceding the cursor.
585 \item{\verb+<g|p>[table#]/cursor+}\\
586 remove the cursor and append the $\SLDROP$ to the \TABLE{} node
588 %********************************* the cursor's parent is a script ******************************
590 %rule handling the case where the script's base is an empty group with id.
591 \item{\verb+<sp|sb>[^(g[@id][^$])#$]/cursor+}\\
592 replace the \SP{} or \SB{} node with the \G{} node and insert the cursor after it.
593 %rule handling the case where the script's base is an empty group without id
594 \item{\verb+<sp|sb>[^(g[^$])#$]/cursor+}\\
595 replace the \SP{} or \SB{} node with the cursor.
596 %rule handling the case where the scrip's base is something else
597 \item{\verb+<sp|sb>[^*#$]/cursor+}\\
598 replace the \SP{} or \SB{} node with it's first child and insert the cursor after it.
600 %********************************* the cursor's parent is a macro ********************************
602 %rule handling the case where the preceding node is a parameter
603 \item{\verb+c[p#]/cursor+}\\
604 remove the cursor and append the $\SLDROP$ to the PNODE{} node.
605 %rule handling the case where the preceding node is a delimiter
606 \item{\verb+c[(<i|n|o|s|c>)#]/cursor+}\\
607 remove the cursor and insert the it before the \INODE{}, \NNODE{}, \ONODE{}, \SNODE{} or \CNODE{} node.
609 %*************************************************************************************************
610 %*********** rules handling the case in which the cursor has no preceding nodes ******************
611 %*************************************************************************************************
613 %rule handling the case where the cursor has something else after it
614 \item{\verb+<g|p>[#*]/cursor+}\\
617 %rules handling the case where the cursor's parent is a p node and the cursor has no nodes after it.
619 %rule handling the case where the p node is a left and right open macro's child and the first p node has no elements.
620 \item{\verb+c[^(p[@left-open='1'][^$])#$]/p[@right-open='1'][^#$]/cursor+}\\
621 replace the \CNODE{} with the cursor.
622 %rule handling the case where the p node is a left and right open macro's child and the first p node has elements.
623 \item{\verb+c[^(p[@left-open='1']#$]/p[@right-open='1'][^#$]/cursor+}\\
624 replace the \CNODE{} with the content of the PNODE{} with attribute texttt{left-open='1'} and insert cursor after this.
625 %rule handling the case where the p node is right open macro's child.
626 \item{\verb+c[^#$]/p[@right-open='1'][^#$]/cursor+}\\
627 replace the \CNODE{} with the cursor.
628 %rule handling the case where the p node is a macro's child and this macro has parameter.
629 \item{\verb+c/p[^#$]/cursor+}\\
630 remove the cursor and insert the $\SLDROP$ before the \PNODE{} node.
632 %rule handling the case where the cursor has no nodes after it and its parent is a group with id
633 \item{\verb+g[@id][^#$]/cursor+}\\
634 replace the \G{} node with the cursor.
638 \section{Right Drop Rules}
640 \section{$\varepsilon$-rules}
642 \paragraph{Nromal Left Drop}
646 %********************* epsilon rules concerning the rgreplace_father ********************
648 \item{\verb+(g[@id][^#$]/++\verb+)+$\RGROUP$}\\
649 replace the whole fragment with the cursor.
651 \item{\verb+*[!@id]/+$\RGROUP$}\\
652 replace the $\RGROUP$ with the cursor.
654 \item{\verb+g[@id][*#]/+$\RGROUP$}\\
655 replace the $\RGROUP$ with the cursor
657 \item{\verb+g[@id][#*]/+$\RGROUP$}\\
658 replace the $\RGROUP$ with the cursor.
659 % maybe it's not the correct action
663 %********************************************* \NLDROP has a preceding node *********************************************
665 %rule handling the case where the preceding node is a token or an empty macro.
666 \item{\verb+*[(i||n||o||s||c[^$])#]/+$\NLDROP$}\\
667 remove the \INODE{}, \NNODE{}, \ONODE{}, \SNODE{} or the \CNODE{} node.
668 %rule handling the case where the preceding node is a group
669 \item{\verb+*[g#]/+$\NLDROP$}\\
670 remove the $\NLDROP$ append it to the \G{} node.
671 %rule handling the case where the preceding node is a script
672 \item{\verb+*[<sp|sb>#]/+$\NLDROP$}\\
673 remove the $\NLDROP$ append it to the \SP{} or \SB{} node.
674 %rule handling the case where the preceding node is an open-right macro
675 \item{\verb+*[(c[^p[@right-open='1']$])#]/+$\NLDROP$}\\
676 remove the $\NLDROP$ and append it to the \PNODE{} node.
677 %rule handling the case where the preceding node is a left-open macro (and not right-open), and the p node of this macro has no children
678 \item{\verb+*[(c[^p[!(@right-open='1')][@left-open='1'][^$]$])#]/+$\NLDROP$}\\
679 remove the \CNODE node.
680 %rule handling the case where the preceding node is a left-open macro (and not right-open), and the p node of this macro has children
681 \item{\verb+*[(c[^p[!(@right-open='1')][@left-open='1']$])#]/+$\NLDROP$}\\
682 replace the \CNODE{} node with the content of the \PNODE{} node.
683 %rule handling the case where the preceding node is a macro with parameter(s)
684 \item{\verb+*[c#]/+$\NLDROP$}\\
685 remove the $\NLDROP$ and append it to the \CNODE{} node.
687 %rule handling the deletion of primes in superscript
689 %there are more than one prime in the phantom group
690 \item{\verb+sp[!(@id)][*#$]/g[!(@id)][o#]/+$\NLDROP$}\\
691 remove the \ONODE node, remove the $\NLDROP$ and insert the cursor after the \SP{} node.
692 %there is one and only one prime in the phantom group
693 \item{\verb+sp[!(@id)][*#$]/g[!(@id)][^o#]/+$\NLDROP$}\\
694 replace the \SP{} node with it's first child and insert the cursor after it
696 %*** rules handling the case where the \NLDROP's parent is a macro (with parameter) ***
698 %the node preceding the \NLDROP is a delimiter
699 \item{\verb+c[(<i|n|o|s|c>)#]/+$\NLDROP$}\\
700 remove the $\NLDROP$ and insert it before the \INODE{}, \NNODE{}, \ONODE{}, \SNODE{} or \CNODE{} node.
701 %the node preceding the \NLDROP is parameter
702 \item{\verb+c[p#]/+$\NLDROP$}\\
703 remove the $\NLDROP$ and append it to the \PNODE{} node.
705 %********************************************* the \NLDROP has no preceding nodes ****************************************************
707 %if the \NLDROP has no preceding nodes, but has following nodes...
708 \item{\verb+<g|p>[#*]/+$\NLDROP$}\\
709 replace the $\NLDROP$ with the cursor.
710 %rule handling the case where the $\NLDROP$ is the only child of a group with id.
711 \item{\verb+g[@id][^#$]/+$\NLDROP$}\\
712 replace the \G{} node with the $\NLDROP$.
713 %\NLDROP is the first child of a macro with no inserted parameter
714 \item{\verb+c[!(p[*])][^#]/+$\NLDROP$}\\
715 replace the \CNODE{} with the $\NLDROP$.
716 %\NLDROP is the first child of a macro with some inserted parameter
717 \item{\verb+c[p[*]][^#]/+$\NLDROP$}\\
718 put the cursor in the first \PNODE{} node.
721 %**** rule handling the case where the \NLDROP has a preceding token or a preceding empty macro, which is either undefined or empty ****
723 %%the \NLDROP's parent is neither a macro nor a phantom group which in turn is a sp's child and the token is a prime
724 %\item{\verb+*[(i||n||o||s||c[^$])#]/+$\NLDROP$}\\
725 %replace the \INODE{}, \NNODE{}, \SNODE{}, \ONODE{}, \SNODE{} or \CNODE{} node with the cursor and remove the $\NLDROP$.
726 %%the \NLDROP's parent is a macro with argument
727 %\item{\verb+c[((!(p[@left-open='1']))&(!(p[@right-open+'1'])))][(i||n||o||s||c[^$])#]/+$\NLDROP$}\\
728 %remove the $\NLDROP$ and insert it before the \INODE{}, \NNODE{}, \ONODE{}, \SNODE{} or \CNODE{} node.
729 %%rule handling the case where the \NLDROP's parent is a phantom group, which in turn is a sp's child
730 %\item{\verb+sp[!(@id)][^*#$]/g[!(@id)][o#$]/+$\NLDROP$}\\
731 %remove the \ONODE{} node
733 %********************************* rules handling the case where the \NLDROP has a preceding group **************************************
734 \item{\verb+*[g#]/+$\NLDROP$}\\
735 remove the $\NLDROP$ and append it to the \G{} node.
739 \paragraph{Special Left Drop}
743 \item{special left}\\
750 \item{\verb+g/+$\tadvance$}\\
751 replace $\tadvance$ with the cursor
753 \item{\verb+p[#$]/+$\tadvance$}\\ %$
754 put $\tadvance$ after the \PNODE{} node
756 \item{\verb+c[#p]/+$\tadvance$} \\
757 remove $\tadvance$, put the cursor as first child of the \PNODE{} node
759 \item{\verb+c[#*]/+$\tadvance$} \\ %$
760 replace $\tadvance$ with the cursor
762 \item{\verb+c[#$]/+$\tadvance$} \\ %$
763 move $\tadvance$ after the \CNODE{} node
766 \paragraph{Next Parameter}
768 \paragraph{Next Token}
770 %% \begin{description}
771 %% \item{\verb+c[#p]/+$\tnext$} \\
774 % g[@id]/(c[#$][@right-open]/g[!@id][#$]/)+cursor } let p = cursor.parent() in remove; advance(p)
778 % */cursor { let g = new group in replace
780 % g[@id][^#$]/cursor <= cursor.parent().replace(cursor)
781 % g[@id][^#$]/cursor <- cursor
782 % (!g[@id][^#$])[A#B]/(g[@id][^#$]/)+cursor <- (!g[@id][^#$])[A#B]/cursor