===================================================================
RCS file: /cvs/mandoc/eqn.c,v
retrieving revision 1.16
retrieving revision 1.28
diff -u -p -r1.16 -r1.28
--- mandoc/eqn.c	2011/07/21 13:18:24	1.16
+++ mandoc/eqn.c	2011/07/22 14:26:32	1.28
@@ -1,4 +1,4 @@
-/*	$Id: eqn.c,v 1.16 2011/07/21 13:18:24 kristaps Exp $ */
+/*	$Id: eqn.c,v 1.28 2011/07/22 14:26:32 kristaps Exp $ */
 /*
  * Copyright (c) 2011 Kristaps Dzonsons <kristaps@bsd.lv>
  *
@@ -19,6 +19,7 @@
 #endif
 
 #include <assert.h>
+#include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -31,15 +32,94 @@
 #define	EQN_NEST_MAX	 128 /* maximum nesting of defines */
 #define	EQN_MSG(t, x)	 mandoc_msg((t), (x)->parse, (x)->eqn.ln, (x)->eqn.pos, NULL)
 
-struct	eqnpart {
+enum	eqn_rest {
+	EQN_DESCOPE,
+	EQN_ERR,
+	EQN_OK,
+	EQN_EOF
+};
+
+enum	eqn_symt {
+	EQNSYM_alpha,
+	EQNSYM_beta,
+	EQNSYM_chi,
+	EQNSYM_delta,
+	EQNSYM_epsilon,
+	EQNSYM_eta,
+	EQNSYM_gamma,
+	EQNSYM_iota,
+	EQNSYM_kappa,
+	EQNSYM_lambda,
+	EQNSYM_mu,
+	EQNSYM_nu,
+	EQNSYM_omega,
+	EQNSYM_omicron,
+	EQNSYM_phi,
+	EQNSYM_pi,
+	EQNSYM_ps,
+	EQNSYM_rho,
+	EQNSYM_sigma,
+	EQNSYM_tau,
+	EQNSYM_theta,
+	EQNSYM_upsilon,
+	EQNSYM_xi,
+	EQNSYM_zeta,
+	EQNSYM_DELTA,
+	EQNSYM_GAMMA,
+	EQNSYM_LAMBDA,
+	EQNSYM_OMEGA,
+	EQNSYM_PHI,
+	EQNSYM_PI,
+	EQNSYM_PSI,
+	EQNSYM_SIGMA,
+	EQNSYM_THETA,
+	EQNSYM_UPSILON,
+	EQNSYM_XI,
+	EQNSYM_inter,
+	EQNSYM_union,
+	EQNSYM_prod,
+	EQNSYM_int,
+	EQNSYM_sum,
+	EQNSYM_grad,
+	EQNSYM_del,
+	EQNSYM_times,
+	EQNSYM_cdot,
+	EQNSYM_nothing,
+	EQNSYM_approx,
+	EQNSYM_prime,
+	EQNSYM_half,
+	EQNSYM_partial,
+	EQNSYM_inf,
+	EQNSYM_muchgreat,
+	EQNSYM_muchless,
+	EQNSYM_larrow,
+	EQNSYM_rarrow,
+	EQNSYM_pm,
+	EQNSYM_nequal,
+	EQNSYM_equiv,
+	EQNSYM_lessequal,
+	EQNSYM_moreequal,
+	EQNSYM__MAX
+};
+
+struct	eqnstr {
 	const char	*name;
 	size_t		 sz;
+};
+
+#define	STRNEQ(p1, sz1, p2, sz2) \
+	((sz1) == (sz2) && 0 == strncmp((p1), (p2), (sz1)))
+#define	EQNSTREQ(x, p, sz) \
+	STRNEQ((x)->name, (x)->sz, (p), (sz))
+
+struct	eqnpart {
+	struct eqnstr	 str;
 	int		(*fp)(struct eqn_node *);
 };
 
-struct	eqnmark {
-	const char	*name;
-	size_t		 sz;
+struct	eqnsym {
+	struct eqnstr	 str;
+	const char	*sym;
 };
 
 enum	eqnpartt {
@@ -49,26 +129,29 @@ enum	eqnpartt {
 	EQN__MAX
 };
 
+static	enum eqn_rest	 eqn_box(struct eqn_node *, struct eqn_box *);
+static	struct eqn_box	*eqn_box_alloc(struct eqn_box *);
 static	void		 eqn_box_free(struct eqn_box *);
 static	struct eqn_def	*eqn_def_find(struct eqn_node *, 
 				const char *, size_t);
 static	int		 eqn_do_define(struct eqn_node *);
 static	int		 eqn_do_set(struct eqn_node *);
 static	int		 eqn_do_undef(struct eqn_node *);
+static	enum eqn_rest	 eqn_eqn(struct eqn_node *, struct eqn_box *);
+static	enum eqn_rest	 eqn_list(struct eqn_node *, struct eqn_box *);
 static	const char	*eqn_nexttok(struct eqn_node *, size_t *);
 static	const char	*eqn_nextrawtok(struct eqn_node *, size_t *);
 static	const char	*eqn_next(struct eqn_node *, 
 				char, size_t *, int);
-static	int		 eqn_box(struct eqn_node *, 
-				struct eqn_box *, struct eqn_box **);
+static	void		 eqn_rewind(struct eqn_node *);
 
 static	const struct eqnpart eqnparts[EQN__MAX] = {
-	{ "define", 6, eqn_do_define }, /* EQN_DEFINE */
-	{ "set", 3, eqn_do_set }, /* EQN_SET */
-	{ "undef", 5, eqn_do_undef }, /* EQN_UNDEF */
+	{ { "define", 6 }, eqn_do_define }, /* EQN_DEFINE */
+	{ { "set", 3 }, eqn_do_set }, /* EQN_SET */
+	{ { "undef", 5 }, eqn_do_undef }, /* EQN_UNDEF */
 };
 
-static	const struct eqnmark eqnmarks[EQNMARK__MAX] = {
+static	const struct eqnstr eqnmarks[EQNMARK__MAX] = {
 	{ "", 0 }, /* EQNMARK_NONE */
 	{ "dot", 3 }, /* EQNMARK_DOT */
 	{ "dotdot", 6 }, /* EQNMARK_DOTDOT */
@@ -80,6 +163,91 @@ static	const struct eqnmark eqnmarks[EQNMARK__MAX] = {
 	{ "under", 5 }, /* EQNMARK_UNDER */
 };
 
+static	const struct eqnstr eqnfonts[EQNFONT__MAX] = {
+	{ "", 0 }, /* EQNFONT_NONE */
+	{ "roman", 5 }, /* EQNFONT_ROMAN */
+	{ "bold", 4 }, /* EQNFONT_BOLD */
+	{ "italic", 6 }, /* EQNFONT_ITALIC */
+};
+
+static	const struct eqnstr eqnposs[EQNPOS__MAX] = {
+	{ "", 0 }, /* EQNPOS_NONE */
+	{ "over", 4 }, /* EQNPOS_OVER */
+	{ "sup", 3 }, /* EQNPOS_SUP */
+	{ "sub", 3 }, /* EQNPOS_SUB */
+	{ "to", 2 }, /* EQNPOS_TO */
+	{ "from", 4 }, /* EQNPOS_FROM */
+};
+
+static	const struct eqnstr eqnpiles[EQNPILE__MAX] = {
+	{ "", 0 }, /* EQNPILE_NONE */
+	{ "cpile", 5 }, /* EQNPILE_CPILE */
+	{ "rpile", 5 }, /* EQNPILE_RPILE */
+	{ "lpile", 5 }, /* EQNPILE_LPILE */
+};
+
+static	const struct eqnsym eqnsyms[EQNSYM__MAX] = {
+	{ { "alpha", 5 }, "*a" }, /* EQNSYM_alpha */
+	{ { "beta", 4 }, "*b" }, /* EQNSYM_beta */
+	{ { "chi", 3 }, "*x" }, /* EQNSYM_chi */
+	{ { "delta", 5 }, "*d" }, /* EQNSYM_delta */
+	{ { "epsilon", 7 }, "*e" }, /* EQNSYM_epsilon */
+	{ { "eta", 3 }, "*y" }, /* EQNSYM_eta */
+	{ { "gamma", 5 }, "*g" }, /* EQNSYM_gamma */
+	{ { "iota", 4 }, "*i" }, /* EQNSYM_iota */
+	{ { "kappa", 5 }, "*k" }, /* EQNSYM_kappa */
+	{ { "lambda", 6 }, "*l" }, /* EQNSYM_lambda */
+	{ { "mu", 2 }, "*m" }, /* EQNSYM_mu */
+	{ { "nu", 2 }, "*n" }, /* EQNSYM_nu */
+	{ { "omega", 5 }, "*w" }, /* EQNSYM_omega */
+	{ { "omicron", 7 }, "*o" }, /* EQNSYM_omicron */
+	{ { "phi", 3 }, "*f" }, /* EQNSYM_phi */
+	{ { "pi", 2 }, "*p" }, /* EQNSYM_pi */
+	{ { "psi", 2 }, "*q" }, /* EQNSYM_psi */
+	{ { "rho", 3 }, "*r" }, /* EQNSYM_rho */
+	{ { "sigma", 5 }, "*s" }, /* EQNSYM_sigma */
+	{ { "tau", 3 }, "*t" }, /* EQNSYM_tau */
+	{ { "theta", 5 }, "*h" }, /* EQNSYM_theta */
+	{ { "upsilon", 7 }, "*u" }, /* EQNSYM_upsilon */
+	{ { "xi", 2 }, "*c" }, /* EQNSYM_xi */
+	{ { "zeta", 4 }, "*z" }, /* EQNSYM_zeta */
+	{ { "DELTA", 5 }, "*D" }, /* EQNSYM_DELTA */
+	{ { "GAMMA", 5 }, "*G" }, /* EQNSYM_GAMMA */
+	{ { "LAMBDA", 6 }, "*L" }, /* EQNSYM_LAMBDA */
+	{ { "OMEGA", 5 }, "*W" }, /* EQNSYM_OMEGA */
+	{ { "PHI", 3 }, "*F" }, /* EQNSYM_PHI */
+	{ { "PI", 2 }, "*P" }, /* EQNSYM_PI */
+	{ { "PSI", 3 }, "*Q" }, /* EQNSYM_PSI */
+	{ { "SIGMA", 5 }, "*S" }, /* EQNSYM_SIGMA */
+	{ { "THETA", 5 }, "*H" }, /* EQNSYM_THETA */
+	{ { "UPSILON", 7 }, "*U" }, /* EQNSYM_UPSILON */
+	{ { "XI", 2 }, "*C" }, /* EQNSYM_XI */
+	{ { "inter", 5 }, "ca" }, /* EQNSYM_inter */
+	{ { "union", 5 }, "cu" }, /* EQNSYM_union */
+	{ { "prod", 4 }, "product" }, /* EQNSYM_prod */
+	{ { "int", 3 }, "integral" }, /* EQNSYM_int */
+	{ { "sum", 3 }, "sum" }, /* EQNSYM_sum */
+	{ { "grad", 4 }, "gr" }, /* EQNSYM_grad */
+	{ { "del", 3 }, "gr" }, /* EQNSYM_del */
+	{ { "times", 5 }, "mu" }, /* EQNSYM_times */
+	{ { "cdot", 4 }, "pc" }, /* EQNSYM_cdot */
+	{ { "nothing", 7 }, "&" }, /* EQNSYM_nothing */
+	{ { "approx", 6 }, "~~" }, /* EQNSYM_approx */
+	{ { "prime", 5 }, "aq" }, /* EQNSYM_prime */
+	{ { "half", 4 }, "12" }, /* EQNSYM_half */
+	{ { "partial", 7 }, "pd" }, /* EQNSYM_partial */
+	{ { "inf", 3 }, "if" }, /* EQNSYM_inf */
+	{ { ">>", 2 }, ">>" }, /* EQNSYM_muchgreat */
+	{ { "<<", 2 }, "<<" }, /* EQNSYM_muchless */
+	{ { "<-", 2 }, "<-" }, /* EQNSYM_larrow */
+	{ { "->", 2 }, "->" }, /* EQNSYM_rarrow */
+	{ { "+-", 2 }, "+-" }, /* EQNSYM_pm */
+	{ { "!=", 2 }, "!=" }, /* EQNSYM_nequal */
+	{ { "==", 2 }, "==" }, /* EQNSYM_equiv */
+	{ { "<=", 2 }, "<=" }, /* EQNSYM_lessequal */
+	{ { ">=", 2 }, ">=" }, /* EQNSYM_moreequal */
+};
+
 /* ARGSUSED */
 enum rofferr
 eqn_read(struct eqn_node **epp, int ln, 
@@ -137,111 +305,229 @@ eqn_alloc(int pos, int line, struct mparse *parse)
 enum rofferr
 eqn_end(struct eqn_node *ep)
 {
-	struct eqn_box	*root, *last;
-	int		 c;
+	struct eqn_box	*root;
+	enum eqn_rest	 c;
 
-	ep->eqn.root = root = 
-		mandoc_calloc(1, sizeof(struct eqn_box));
+	ep->eqn.root = mandoc_calloc(1, sizeof(struct eqn_box));
+
+	root = ep->eqn.root;
 	root->type = EQN_ROOT;
 
 	if (0 == ep->sz)
 		return(ROFF_IGN);
 
-	/*
-	 * Run the parser.
-	 * If we return before reaching the end of our input, our scope
-	 * is still open somewhere.
-	 * If we return alright but don't have a symmetric scoping, then
-	 * something's not right either.
-	 * Otherwise, return the equation.
-	 */
+	if (EQN_DESCOPE == (c = eqn_eqn(ep, root))) {
+		EQN_MSG(MANDOCERR_EQNNSCOPE, ep);
+		c = EQN_ERR;
+	}
 
-	if (0 == (c = eqn_box(ep, root, &last))) {
-		if (last != root) {
+	return(EQN_EOF == c ? ROFF_EQN : ROFF_IGN);
+}
+
+static enum eqn_rest
+eqn_eqn(struct eqn_node *ep, struct eqn_box *last)
+{
+	struct eqn_box	*bp;
+	enum eqn_rest	 c;
+
+	bp = eqn_box_alloc(last);
+	bp->type = EQN_SUBEXPR;
+
+	while (EQN_OK == (c = eqn_box(ep, bp)))
+		/* Spin! */ ;
+
+	return(c);
+}
+
+static enum eqn_rest
+eqn_list(struct eqn_node *ep, struct eqn_box *last)
+{
+	struct eqn_box	*bp;
+	const char	*start;
+	size_t		 sz;
+	enum eqn_rest	 c;
+
+	bp = eqn_box_alloc(last);
+	bp->type = EQN_LIST;
+
+	if (NULL == (start = eqn_nexttok(ep, &sz))) {
+		EQN_MSG(MANDOCERR_EQNEOF, ep);
+		return(EQN_ERR);
+	}
+	if ( ! STRNEQ(start, sz, "{", 1)) {
+		EQN_MSG(MANDOCERR_EQNSYNT, ep);
+		return(EQN_ERR);
+	}
+
+	while (EQN_DESCOPE == (c = eqn_eqn(ep, bp))) {
+		eqn_rewind(ep);
+		start = eqn_nexttok(ep, &sz);
+		assert(start);
+		if ( ! STRNEQ(start, sz, "above", 5))
+			break;
+		bp->last->above = 1;
+	}
+
+	if (EQN_DESCOPE != c) {
+		if (EQN_ERR != c)
 			EQN_MSG(MANDOCERR_EQNSCOPE, ep);
-			c = 0;
-		}
-	} else if (c > 0)
-		EQN_MSG(MANDOCERR_EQNNSCOPE, ep);
+		return(EQN_ERR);
+	}
 
-	return(0 == c ? ROFF_EQN : ROFF_IGN);
+	eqn_rewind(ep);
+	start = eqn_nexttok(ep, &sz);
+	assert(start);
+	if (STRNEQ(start, sz, "}", 1))
+		return(EQN_OK);
+
+	EQN_MSG(MANDOCERR_EQNBADSCOPE, ep);
+	return(EQN_ERR);
 }
 
-static int
-eqn_box(struct eqn_node *ep, struct eqn_box *last, struct eqn_box **sv)
+static enum eqn_rest
+eqn_box(struct eqn_node *ep, struct eqn_box *last)
 {
 	size_t		 sz;
 	const char	*start;
-	int		 c, i, nextc;
+	char		*left;
+	char		 sym[64];
+	enum eqn_rest	 c;
+	int		 i, size;
 	struct eqn_box	*bp;
 
-	/* 
-	 * Mark our last level of subexpression. 
-	 * Also mark whether that the next node should be a
-	 * subexpression node.
-	 */
-
-	*sv = last;
-	nextc = 1;
-again:
 	if (NULL == (start = eqn_nexttok(ep, &sz)))
-		return(0);
+		return(EQN_EOF);
 
+	if (STRNEQ(start, sz, "}", 1))
+		return(EQN_DESCOPE);
+	else if (STRNEQ(start, sz, "right", 5))
+		return(EQN_DESCOPE);
+	else if (STRNEQ(start, sz, "above", 5))
+		return(EQN_DESCOPE);
+
 	for (i = 0; i < (int)EQN__MAX; i++) {
-		if (eqnparts[i].sz != sz)
+		if ( ! EQNSTREQ(&eqnparts[i].str, start, sz))
 			continue;
-		if (strncmp(eqnparts[i].name, start, sz))
-			continue;
-		if ( ! (*eqnparts[i].fp)(ep))
-			return(-1);
+		return((*eqnparts[i].fp)(ep) ? EQN_OK : EQN_ERR);
+	} 
 
-		goto again;
+	if (STRNEQ(start, sz, "{", 1)) {
+		if (EQN_DESCOPE != (c = eqn_eqn(ep, last))) {
+			if (EQN_ERR != c)
+				EQN_MSG(MANDOCERR_EQNSCOPE, ep);
+			return(EQN_ERR);
+		}
+		eqn_rewind(ep);
+		start = eqn_nexttok(ep, &sz);
+		assert(start);
+		if (STRNEQ(start, sz, "}", 1))
+			return(EQN_OK);
+		EQN_MSG(MANDOCERR_EQNBADSCOPE, ep);
+		return(EQN_ERR);
 	} 
 
-	for (i = 0; i < (int)EQNMARK__MAX; i++) {
-		if (eqnmarks[i].sz != sz)
+	for (i = 0; i < (int)EQNPILE__MAX; i++) {
+		if ( ! EQNSTREQ(&eqnpiles[i], start, sz))
 			continue;
-		if (strncmp(eqnmarks[i].name, start, sz))
-			continue;
-		last->mark = (enum eqn_markt)i;
-		goto again;
+		if (EQN_OK == (c = eqn_list(ep, last)))
+			last->last->pile = (enum eqn_pilet)i;
+		return(c);
 	}
 
-	/* Exit this [hopefully] subexpression. */
+	if (STRNEQ(start, sz, "left", 4)) {
+		if (NULL == (start = eqn_nexttok(ep, &sz))) {
+			EQN_MSG(MANDOCERR_EQNEOF, ep);
+			return(EQN_ERR);
+		}
+		left = mandoc_strndup(start, sz);
+		c = eqn_eqn(ep, last);
+		if (last->last)
+			last->last->left = left;
+		else
+			free(left);
+		if (EQN_DESCOPE != c)
+			return(c);
+		assert(last->last);
+		eqn_rewind(ep);
+		start = eqn_nexttok(ep, &sz);
+		assert(start);
+		if ( ! STRNEQ(start, sz, "right", 5))
+			return(EQN_DESCOPE);
+		if (NULL == (start = eqn_nexttok(ep, &sz))) {
+			EQN_MSG(MANDOCERR_EQNEOF, ep);
+			return(EQN_ERR);
+		}
+		last->last->right = mandoc_strndup(start, sz);
+		return(EQN_OK);
+	}
 
-	if (sz == 1 && 0 == strncmp("}", start, 1)) 
-		return(1);
+	for (i = 0; i < (int)EQNPOS__MAX; i++) {
+		if ( ! EQNSTREQ(&eqnposs[i], start, sz))
+			continue;
+		if (NULL == last->last) {
+			EQN_MSG(MANDOCERR_EQNSYNT, ep);
+			return(EQN_ERR);
+		} 
+		last->last->pos = (enum eqn_post)i;
+		if (EQN_EOF == (c = eqn_box(ep, last))) {
+			EQN_MSG(MANDOCERR_EQNEOF, ep);
+			return(EQN_ERR);
+		}
+		return(c);
+	}
 
-	bp = mandoc_calloc(1, sizeof(struct eqn_box));
-	if (nextc)
-		last->child = bp;
-	else
-		last->next = bp;
+	for (i = 0; i < (int)EQNMARK__MAX; i++) {
+		if ( ! EQNSTREQ(&eqnmarks[i], start, sz))
+			continue;
+		if (NULL == last->last) {
+			EQN_MSG(MANDOCERR_EQNSYNT, ep);
+			return(EQN_ERR);
+		} 
+		last->last->mark = (enum eqn_markt)i;
+		if (EQN_EOF == (c = eqn_box(ep, last))) {
+			EQN_MSG(MANDOCERR_EQNEOF, ep);
+			return(EQN_ERR);
+		}
+		return(c);
+	}
 
-	last = bp;
+	for (i = 0; i < (int)EQNFONT__MAX; i++) {
+		if ( ! EQNSTREQ(&eqnfonts[i], start, sz))
+			continue;
+		if (EQN_EOF == (c = eqn_box(ep, last))) {
+			EQN_MSG(MANDOCERR_EQNEOF, ep);
+			return(EQN_ERR);
+		} else if (EQN_OK == c)
+			last->last->font = (enum eqn_fontt)i;
+		return(c);
+	}
 
-	/* 
-	 * See if we're to open a new subexpression.
-	 * If so, mark our node as such and descend.
-	 */
-
-	if (sz == 1 && 0 == strncmp("{", start, 1)) {
-		bp->type = EQN_SUBEXPR;
-		c = eqn_box(ep, bp, sv);
-
-		nextc = 0;
-		goto again;
+	if (STRNEQ(start, sz, "size", 4)) {
+		if (NULL == (start = eqn_nexttok(ep, &sz))) {
+			EQN_MSG(MANDOCERR_EQNEOF, ep);
+			return(EQN_ERR);
+		}
+		size = mandoc_strntoi(start, sz, 10);
+		if (EQN_EOF == (c = eqn_box(ep, last))) {
+			EQN_MSG(MANDOCERR_EQNEOF, ep);
+			return(EQN_ERR);
+		} else if (EQN_OK != c)
+			return(c);
+		last->last->size = size;
 	}
 
-	/* A regular text node. */
-
+	bp = eqn_box_alloc(last);
 	bp->type = EQN_TEXT;
-	bp->text = mandoc_malloc(sz + 1);
-	*bp->text = '\0';
-	strlcat(bp->text, start, sz + 1);
+	for (i = 0; i < (int)EQNSYM__MAX; i++)
+		if (EQNSTREQ(&eqnsyms[i].str, start, sz)) {
+			sym[63] = '\0';
+			snprintf(sym, 62, "\\[%s]", eqnsyms[i].sym);
+			bp->text = mandoc_strdup(sym);
+			return(EQN_OK);
+		}
 
-	nextc = 0;
-	goto again;
+	bp->text = mandoc_strndup(start, sz);
+	return(EQN_OK);
 }
 
 void
@@ -261,16 +547,36 @@ eqn_free(struct eqn_node *p)
 	free(p);
 }
 
+static struct eqn_box *
+eqn_box_alloc(struct eqn_box *parent)
+{
+	struct eqn_box	*bp;
+
+	bp = mandoc_calloc(1, sizeof(struct eqn_box));
+	bp->parent = parent;
+	bp->size = EQN_DEFSIZE;
+
+	if (NULL == parent->first)
+		parent->first = bp;
+	else
+		parent->last->next = bp;
+
+	parent->last = bp;
+	return(bp);
+}
+
 static void
 eqn_box_free(struct eqn_box *bp)
 {
 
-	if (bp->child)
-		eqn_box_free(bp->child);
+	if (bp->first)
+		eqn_box_free(bp->first);
 	if (bp->next)
 		eqn_box_free(bp->next);
 
 	free(bp->text);
+	free(bp->left);
+	free(bp->right);
 	free(bp);
 }
 
@@ -288,19 +594,26 @@ eqn_nexttok(struct eqn_node *ep, size_t *sz)
 	return(eqn_next(ep, '"', sz, 1));
 }
 
+static void
+eqn_rewind(struct eqn_node *ep)
+{
+
+	ep->cur = ep->rew;
+}
+
 static const char *
 eqn_next(struct eqn_node *ep, char quote, size_t *sz, int repl)
 {
 	char		*start, *next;
 	int		 q, diff, lim;
-	size_t		 sv, ssz;
+	size_t		 ssz, dummy;
 	struct eqn_def	*def;
 
 	if (NULL == sz)
-		sz = &ssz;
+		sz = &dummy;
 
 	lim = 0;
-	sv = ep->cur;
+	ep->rew = ep->cur;
 again:
 	/* Prevent self-definitions. */
 
@@ -309,7 +622,7 @@ again:
 		return(NULL);
 	}
 
-	ep->cur = sv;
+	ep->cur = ep->rew;
 	start = &ep->data[(int)ep->cur];
 	q = 0;
 
@@ -322,14 +635,26 @@ again:
 	}
 
 	start = &ep->data[(int)ep->cur];
-	next = q ? strchr(start, quote) : strchr(start, ' ');
 
+	if ( ! q) {
+		if ('{' == *start || '}' == *start)
+			ssz = 1;
+		else
+			ssz = strcspn(start + 1, " ~\"{}\t") + 1;
+		next = start + (int)ssz;
+		if ('\0' == *next)
+			next = NULL;
+	} else
+		next = strchr(start, quote);
+
 	if (NULL != next) {
 		*sz = (size_t)(next - start);
 		ep->cur += *sz;
 		if (q)
 			ep->cur++;
-		while (' ' == ep->data[(int)ep->cur])
+		while (' ' == ep->data[(int)ep->cur] ||
+				'\t' == ep->data[(int)ep->cur] ||
+				'~' == ep->data[(int)ep->cur])
 			ep->cur++;
 	} else {
 		if (q)
@@ -351,7 +676,7 @@ again:
 			ep->sz += diff;
 			ep->data = mandoc_realloc(ep->data, ep->sz + 1);
 			ep->data[ep->sz] = '\0';
-			start = &ep->data[(int)sv];
+			start = &ep->data[(int)ep->rew];
 		}
 
 		diff = def->valsz - *sz;
@@ -456,8 +781,8 @@ eqn_def_find(struct eqn_node *ep, const char *key, siz
 	int		 i;
 
 	for (i = 0; i < (int)ep->defsz; i++) 
-		if (ep->defs[i].keysz && ep->defs[i].keysz == sz &&
-				0 == strncmp(ep->defs[i].key, key, sz))
+		if (ep->defs[i].keysz && STRNEQ(ep->defs[i].key, 
+					ep->defs[i].keysz, key, sz))
 			return(&ep->defs[i]);
 
 	return(NULL);