Pikchr

  unsigned nErr;           /* Number of errors seen */
  const char *zIn;         /* Input PIKCHR-language text.  zero-terminated */
  unsigned int nIn;        /* Number of bytes in zIn */
  char *zOut;              /* Result accumulates here */
  unsigned int nOut;       /* Bytes written to zOut[] so far */
  unsigned int nOutAlloc;  /* Space allocated to zOut[] */
  unsigned char eDir;      /* Current direction */
  unsigned int mFlags;     /* Flags passed to pikchr() */
  PElem *cur;              /* Element under construction */
  PEList *list;            /* Element list under construction */
  PVar *pVar;              /* Application-defined variables */
  PBox bbox;               /* Bounding box around all elements */
                           /* Cache of layout values.  <=0.0 for unknown... */
  PNum rScale;                 /* Multiply to convert inches to pixels */
  PNum fontScale;              /* Scale fonts by this percent */

  pik_append(p, buf, -1);
}

/* Append a style="..." text.  But, leave the quote unterminated, in case
** the caller wants to add some more.
*/
static void pik_append_style(Pik *p, PElem *pElem){
  pik_append(p, "style=\"", -1);
  pik_append(p, " style=\"", -1);
  if( pElem->fill>=0 ){
    pik_append_clr(p, "fill:", pElem->fill, ";");
  }else{
    pik_append(p,"fill:none;",-1);
  }
  if( pElem->sw>0.0 && pElem->color>=0.0 ){
    PNum sw = pElem->sw;

  return 0;
}

/*
** Process an "assert( place1 == place2 )" statement.  Always return NULL.
*/
static PElem *pik_place_assert(Pik *p, PPoint *e1, PToken *pEq, PPoint *e2){
  char zE1[100], zE2[100], zMsg[200];
  char zE1[100], zE2[100], zMsg[210];

  /* Convert the numbers to strings using %g for comparison.  This
  ** limits the precision of the comparison to account for rounding error. */
  snprintf(zE1, sizeof(zE1), "(%g,%g)", e1->x, e1->y); zE1[sizeof(zE1)-1] = 0;
  snprintf(zE2, sizeof(zE2), "(%g,%g)", e2->x, e2->y); zE1[sizeof(zE2)-1] = 0;
  if( strcmp(zE1,zE2)!=0 ){
    snprintf(zMsg, sizeof(zMsg), "%s != %s", zE1, zE2);

    }
    w = p->bbox.ne.x - p->bbox.sw.x;
    h = p->bbox.ne.y - p->bbox.sw.y;
    p->wSVG = (int)(p->rScale*w);
    p->hSVG = (int)(p->rScale*h);
    pik_append_dis(p, " viewBox=\"0 0 ",w,"");
    pik_append_dis(p, " ",h,"\">\n");
    if(1){
      /* emit original pikchr source code as metadata */
      /* FIXME: emit this only if a certain p->mFlags is set. */
      pik_append(p, "<metadata>\n", 11);
      pik_append(p, "<pikchr:pikchr xmlns:pikchr="
         "\"https://pikchr.org/home/doc/trunk/doc/grammar.md\">\n",
          -1);
      pik_append(p, "<pikchr:src><![CDATA[", 21);
      pik_append(p, p->zIn, (int)p->nIn);
      pik_append(p, "]]></pikchr:src>\n", 17);
      pik_append(p, "</pikchr:pikchr>\n", 17);
      pik_append(p, "</metadata>\n", 12);
    }
    pik_elist_render(p, pEList);
    pik_append(p,"</svg>\n", -1);
  }else{
    p->wSVG = -1;
    p->hSVG = -1;
  }
  pik_elist_free(p, pEList);

  yyParser sParse;

  memset(&s, 0, sizeof(s));
  s.zIn = zText;
  s.nIn = (unsigned int)strlen(zText);
  s.eDir = DIR_RIGHT;
  s.zClass = zClass;
  s.mFlags = mFlags;
  pik_parserInit(&sParse, &s);
#if 0
  pik_parserTrace(stdout, "parser: ");
#endif
  for(i=0; zText[i] && s.nErr==0; i+=sz){
    token.eCode = 0;
    token.eEdge = 0;