1 files changed, 140 insertions, 0 deletions
diff --git a/src/cmd/eqn/eqn.y b/src/cmd/eqn/eqn.y
new file mode 100644
index 00000000..74796d7f
--- /dev/null
+++ b/src/cmd/eqn/eqn.y
@@ -0,0 +1,140 @@
+%term	CONTIG QTEXT SPACE THIN TAB
+%term	MATRIX LCOL CCOL RCOL COL ABOVE
+%term	MARK LINEUP
+%term	SUM INT PROD UNION INTER
+%term	DEFINE TDEFINE NDEFINE DELIM GSIZE GFONT INCLUDE SPACE IFDEF
+%term	DOTEQ DOTEN
+
+%right	FROM TO
+%left	OVER SQRT
+%right	SUP SUB
+%right	SIZE FONT ROMAN ITALIC BOLD FAT
+%right	UP DOWN BACK FWD
+%left	LEFT RIGHT
+%right	DOT DOTDOT HAT TILDE BAR LOWBAR HIGHBAR UNDER VEC DYAD UTILDE
+
+%{
+#include "e.h"
+
+int	yylex(void);
+%}
+
+%%
+
+stuff	: eqn 		{ putout($1); }
+	| error		{ ERROR "syntax error" WARNING; }	/* should be SYNTAX */
+	|		{ eqnreg = 0; }
+	;
+
+eqn	: box
+	| eqn box	{ eqnbox($1, $2, 0); }
+	| eqn lineupbox	{ eqnbox($1, $2, 1); }
+	| LINEUP	{ lineup(0); }
+	;
+
+lineupbox: LINEUP box	{ $$ = $2; lineup(1); }
+	;
+
+sbox	: SUP box	%prec SUP	{ $$ = $2; }
+	|		%prec SUP	{ $$ = 0; }
+	;
+
+tbox	: TO box	%prec TO	{ $$ = $2; }
+	|		%prec FROM	{ $$ = 0; }
+	;
+
+box	: '{' eqn '}'	{ $$ = $2; }
+	| QTEXT		{ text(QTEXT, (char *) $1); }
+	| CONTIG	{ text(CONTIG, (char *) $1); }
+	| SPACE		{ text(SPACE, (char *) 0); }
+	| THIN		{ text(THIN, (char *) 0); }
+	| TAB		{ text(TAB, (char *) 0); }
+	| SUM		{ funny(SUM); }
+	| PROD		{ funny(PROD); }
+	| UNION		{ funny(UNION); }
+	| INTER		{ funny(INTER); }
+ 	| box OVER box			{ boverb($1, $3); }
+	| MARK box			{ mark($2); }
+	| size box	%prec SIZE	{ size($1, $2); }
+	| font box	%prec FONT	{ font($1, $2); }
+	| FAT box			{ fatbox($2); }
+	| SQRT box			{ sqrt($2); }
+	| box SUB {ps -= deltaps;} box sbox	%prec SUB	{ subsup($1, $4, $5); }
+	| box SUP {ps -= deltaps;} box		%prec SUP	{ subsup($1, 0, $4); }
+	| int SUB {ps -= deltaps;} box sbox	%prec SUB	{ integral($1, $4, $5); }
+	| int SUP {ps -= deltaps;} box		%prec SUP	{ integral($1, 0, $4); }
+	| int					{ integral($1, 0, 0); }
+	| box FROM {ps -= deltaps;} box tbox	%prec FROM	{ fromto($1, $4, $5); }
+	| box TO {ps -= deltaps;} box		%prec TO	{ fromto($1, 0, $4); }
+	| left eqn right			{ paren($1, $2, $3); }
+	| left eqn 				{ paren($1, $2, 0); }
+	| box diacrit			{ diacrit($1, $2); }
+	| fwd box	%prec UP	{ move(FWD, $1, $2); }
+	| up box	%prec UP	{ move(UP, $1, $2); }
+	| back box	%prec UP	{ move(BACK, $1, $2); }
+	| down box	%prec UP	{ move(DOWN, $1, $2); }
+	| column			{ pile($1); ct = $1; }
+	| MATRIX {$$=ct;} '{' collist '}'	{ matrix($2); ct = $2; }
+	;
+
+int	: INT		{ setintegral(); }
+	;
+
+fwd	: FWD text	{ $$ = atoi((char *) $1); } ;
+up	: UP text	{ $$ = atoi((char *) $1); } ;
+back	: BACK text	{ $$ = atoi((char *) $1); } ;
+down	: DOWN text	{ $$ = atoi((char *) $1); } ;
+
+diacrit	: HAT		{ $$ = HAT; }
+	| VEC		{ $$ = VEC; }
+	| DYAD		{ $$ = DYAD; }
+	| BAR		{ $$ = BAR; }
+	| LOWBAR	{ $$ = LOWBAR; }
+	| HIGHBAR	{ $$ = HIGHBAR; }
+	| UNDER		{ $$ = UNDER; }	/* underbar */
+	| DOT		{ $$ = DOT; }
+	| TILDE		{ $$ = TILDE; }
+	| UTILDE	{ $$ = UTILDE; }
+	| DOTDOT	{ $$ = DOTDOT; } /* umlaut = double dot */
+	;
+
+left	: LEFT text	{ $$ = ((char *)$2)[0]; }
+	| LEFT '{'	{ $$ = '{'; }
+	;
+
+right	: RIGHT text	{ $$ = ((char *)$2)[0]; }
+	| RIGHT '}'	{ $$ = '}'; }
+	;
+
+collist	: column
+	| collist column
+	;
+
+column	: col '{' list '}'				{ column($1, DEFGAP); }
+	| col text {$$=atoi((char*)$2);} '{' list '}'	{ column($1, $3); }
+	;
+
+col	: LCOL		{ $$ = startcol(LCOL); }
+	| CCOL		{ $$ = startcol(CCOL); }
+	| RCOL		{ $$ = startcol(RCOL); }
+	| COL		{ $$ = startcol(COL); }
+	;
+
+list	: eqn			{ lp[ct++] = $1; }
+	| list ABOVE eqn	{ lp[ct++] = $3; }
+	;
+
+size	: SIZE text	{ $$ = ps; setsize((char *) $2); }
+	;
+
+font    : ROMAN         { static char R[]="R"; setfont(R); }
+        | ITALIC        { static char I[]="I"; setfont(I); }
+        | BOLD          { static char B[]="B"; setfont(B); }
+        | FONT text     { setfont((char *)$2); }
+        ;
+
+text	: CONTIG
+	| QTEXT
+	;
+
+%%