Four Years with Decker

But I can definitely relate to the yearning for older, clunkier, "quieter" tech, in this age of ubiquitous HTML, CSS, JS. These maybe seemingly naive assumptions like mixing code and presentation, suboptimal UX, and the fact that people still enjoy developing for them for fun rather than for some SaaS end, feels, I don't know, cozy?

Here, I inserted a subtle bug in this function, can you find it?

    int widget_grid(lv*target,grid x,grid_val*value){
        if(x.show==show_none)return 0; lv*hfnt=FONT_BODY; int hsize=x.headers?font_h(hfnt)+5:0; if(x.size.h<=(50+hsize)||x.size.w<16)x.scrollbar=0;
        lv*fnt=x.font?x.font:FONT_MONO; int os=value->scroll, or=value->row, oc=value->col, files=x.headers==2; if(files||x.size.h<=hsize)x.headers=0;
        int _bg=dgeti(value->table,lmistr("_bg")),_fg=dgeti(value->table,lmistr("_fg")),_hideby=dgeti(value->table,lmistr("_hideby"));
        lv*pv=NULL,*vp=NULL;if(target!=NULL&&_hideby!=-1)grid_pv(target,&pv,&vp);int nr=pv?pv->c: value->table->n;
        #define grid_cell_at(col,row) (value->table->lv[col]->lv[permuted_row(row)])

        int nc=MIN(256,value->table->c), rh=font_h(fnt)+(x.lines?5:3), fcol=!in_layer()?13:x.show==show_invert?32:1, bcol=x.show==show_invert?1:32;
        int fk=strlen(x.format); rect b=x.size;
        int sel=in_layer()&&x.show!=show_none&&wid.active==wid.count;
        if(in_layer()&&dover(b)&&(ev.md||ev.mu||ev.drag)){if(!sel&&wid.gv)grid_exit(); wid.active=wid.count,sel=1;}
        if(sel&&in_layer()&&!over(b)&&ev.md){sel=0;wid.active=-1;grid_exit();}
        if(sel){if(wid.fv)field_exit();wid.ingrid=1,wid.g=x,wid.gv=value,wid.gt=target;}
        if(x.show!=show_transparent)draw_rect(b,bcol);
        rect bh={b.x,b.y,b.w,x.headers?font_h(hfnt)+5:0}; int nrd=MIN(nr,((b.h-bh.h+1)/rh)), scrollmax=nr-nrd;
        rect bb=scrollbar((rect){b.x,b.y+(x.headers?bh.h-1:0),b.w,b.h-(x.headers?bh.h-1:0)},scrollmax,1,nrd,&value->scroll,x.scrollbar,x.show==show_invert);
        draw_box(x.lines?b:(rect){b.x,bb.y,b.w,b.h-(bb.y-b.y)},0,sel?13:fcol);
        char*pal=patterns_pal(ifield(deck,"patterns"));
        if(x.lines)draw_rect(bh,fcol);if(nc<=0)draw_textc(inset(bb,1),"(no data)",hfnt,fcol);

        int cw[256];for(int z=0;z<nc;z++)cw[z]=z>=x.widths[0]?-1:x.widths[1+z];
        if(_bg!=-1)cw[_bg]=0;if(_fg!=-1)cw[_fg]=0;if(_hideby!=-1)cw[_hideby]=0;
        int hwt=0;for(int z=0;z<x.widths[0];z++)hwt+=cw[z];
        int nwt=0;for(int z=0;z<nc         ;z++)nwt+=cw[z]==-1;
        for(int z=x.widths[0];z<nc         ;z++)cw[z]=cw[z]==-1?(bb.w-hwt)/nwt:0;

        if(!cf.sv)cf=str_new();
        #define rowh(n) inset((rect){bb.x+1,bb.y+rh*n+2,bb.w-2,rh-3},x.lines?0:-1)
        #define rowb(n) (rect){bb.x,bb.y+rh*n,bb.w,rh}
        int clicked=0,rsel=0,hrow=-1,hcol=-1;
        for(int y=0;y<nrd;y++){
                if(_bg!=-1){
                        int p=CLAMP(0,ln(grid_cell_at(_bg,y+value->scroll)),255);
                        if(p){rect t=rowb(y);if(y==0)t.y+=1,t.h-=1; draw_rect(t,p);}
                }
                int ra=in_layer()&&over(bb)&&over(rowb(y));rect cbox={0};
                if(ra&&x.bycell){for(int z=0;z<nc;z++){rect cell=grid_cell(x,value,bb,(pair){z,y},cw);if(over(cell))hcol=z,cbox=grid_hcell(x,z,cell);}}
                if(ra&&(ev.md||ev.drag)){rsel=1,hrow=y+value->scroll;draw_rect(x.bycell?cbox:rowh(y),fcol);}
                if(ra&&ev.mu)clicked=1,value->row=permuted_row(y+value->scroll),value->col=hcol;
                if(ra&&!ev.drag)uicursor=cursor_point;
        }int rr=display_row(value->row)-value->scroll;
        if(!rsel&&rr>=0&&rr<nrd&&(x.bycell?value->col>=0&&value->col<nc:1)){
                hrow=display_row(value->row),hcol=value->col;
                if(x.bycell&&value->col>=0){draw_rect(grid_hcell(x,value->col,grid_cell(x,value,bb,(pair){value->col,rr},cw)),fcol);}
                else{draw_rect(rowh(rr),fcol);}
        }
        int drawncol=0;for(int z=0,cols=0,cx=0;z<nc&&cx+cw[cols]<=bb.w;z++,cols++){
                rect hs=(rect){bh.x+4+cx,bh.y+1,cw[cols]-5,bh.h-2};
                if(hs.w<=0)continue; // suppressed column
                if(x.headers){
                        int oa=target&&in_layer()&&over(hs)&&((ev.drag||ev.mu)?dover(hs):1)&&!wid.col_drag;
                        int dp=oa&&(ev.md||ev.drag);if(dp)draw_rect(hs,x.lines?bcol:fcol);
                        draw_textc(hs,value->table->kv[z]->sv,hfnt,x.lines^dp?bcol:fcol);
                        if(oa&&!ev.drag)uicursor=cursor_point;
                        if(oa&&ev.mu){msg.target_order=target,msg.arg_order=value->table->kv[z];}
                }
                if(drawncol&&x.lines)draw_invert(pal,(rect){hs.x-3,b.y+1,1,b.h-2});cx+=cw[cols];drawncol=1;
                for(int y=0;y<nrd;y++){
                        int ccol=y+value->scroll==hrow&&(x.bycell?cols==hcol :1)?bcol: _fg==-1?fcol: CLAMP(0,ln(grid_cell_at(_fg,y+value->scroll)),255);
                        rect cell={hs.x-3,bb.y+rh*y+1,hs.w+5,rh-1}; lv*v=grid_cell_at(z,y+value->scroll);
                        cf.c=0;format_type_simple(&cf,v,z>fk?'s':x.format[z]=='L'?'s':x.format[z]);str_term(&cf);
                        rect ib=box_center(cell,image_size(ICONS[0]));pair ip={ib.x,ib.y};
                        rect oc=frame.clip; frame.clip=box_intersect(cell,frame.clip);
                        if     (z<fk&&x.format[z]=='I'){int i=MAX(0,MIN(8,ln(v)));if(i<8)draw_icon(ip,ICONS[i],ccol);}
                        else if(z<fk&&x.format[z]=='B'){if(lb(v))draw_icon(ip,ICONS[icon_chek],ccol);}
                        else if(z<fk&&(x.format[z]=='t'||x.format[z]=='T')){
                                rect rr={hs.x+1,bb.y+rh*y,hs.w-2,rh}; // display rich text:
                                pair t=layout_richtext(deck,rtext_cast(v),fnt,align_left,rr.w);
                                rect r={rr.x,rr.y+ceil(t.y<rr.h?(rr.h-t.y)/2.0:0),rr.w,rr.h};
                                lv*alink=NULL;if(x.format[z]=='T'&&in_layer()&&(ev.md||ev.drag||ev.mu))for(int z=0;z<layout_count;z++){
                                        glyph_box g=layout[z];if(g.pos.w<1)continue; // skip squashed spaces/newlines
                                        if(g.pos.y+g.pos.h<0||g.pos.y>r.h)continue; g.pos.x+=r.x, g.pos.y+=r.y; // coarse clip
                                        if(lis(g.arg)&&g.arg->c&&dover(g.pos)&&over(g.pos)){
                                                if(ev.md||ev.drag){alink=g.arg;break;}
                                                if(ev.mu){msg.target_link=target,msg.arg_link=g.arg;break;}
                                        }
                                }
                                draw_text_rich_raw(r,ccol,0,alink);
                        }
                        else{
                                rect r={hs.x+1,bb.y+rh*y,hs.w-2,rh}; // right-align numeric columns:
                                if(z<fk&&strchr("fcCihH",x.format[z])){draw_textr(r,cf.sv,fnt,ccol);}else{draw_text_fit(r,cf.sv,fnt,ccol);}
                        }
                        frame.clip=oc;
                        if(!x.locked&&sel&& ((ev.dclick&&over(cell)) || (ev.action&&x.bycell&&z==value->col&&y+value->scroll==display_row(value->row)))){
                                char f=z<fk?x.format[z]:'s';pair tc=(pair){z,y+value->scroll},tpc=(pair){tc.x,permuted_row(tc.y)};
                                if     (f=='I'||f=='L'||f=='T'){} // no editing allowed
                                else if(f=='B'||f=='b'){grid_edit_cell(tpc,ls(lmn(!lb(v))));} // toggle
                                else{
                                        ms.pending_grid_cell_rich=f=='t';
                                        wid.pending_grid_edit=1,ms.pending_grid_cell=grid_cell(x,value,bb,(pair){tc.x,tc.y-value->scroll},cw);
                                        ms.pending_grid_cell.y-=1,ms.pending_grid_cell.w+=1,ms.pending_grid_cell.h+=2;
                                        ms.cell=tpc;ms.text=(field_val){f=='t'?rtext_cast(v):rtext_cast(lmcstr(cf.sv)),0};
                                }
                        }
                }
        }
        if(x.lines)for(int y=1;y<nrd;y++)draw_hline(bb.x,bb.x+bb.w,bb.y+rh*y,fcol);
        if(!x.locked&&in_layer()&&target)for(int z=0,cx=bh.x;z<nc;cx+=cw[z],z++){
                if(cw[z]==0)continue;
                rect h={cx+cw[z]-1,bh.y,5,bh.h};if(h.x+h.w>b.x+b.w)break;
                if(over(h))draw_vline(h.x+2,h.y,h.y+h.h,13);
                if(ev.md&&dover(h)){wid.col_drag=1,wid.col_num=z,wid.col_orig=cw[z];}
                if(sel&&wid.col_drag&&wid.col_num==z&&ev.drag){
                        int s=MIN(MAX(10,wid.col_orig+(ev.pos.x-ev.dpos.x)),bb.w-10),i=z;uicursor=cursor_drag;
                        GEN(r,MAX(x.widths[0],i+1))lmn(i==z?s:cw[z]);iwrite(target,lmistr("widths"),r),mark_dirty();
                }
        }
        if(target&&os!=value->scroll)iwrite(target,lmistr("scroll"),lmn(value->scroll)),mark_dirty();
        if(target&&or!=value->row)iwrite(target,lmistr("row"),lmn(value->row)),mark_dirty();
        if(target&&oc!=value->col)iwrite(target,lmistr("col"),lmn(value->col)),mark_dirty();
        if(target&&clicked)msg.target_click=target,msg.arg_click=(fpair){0,value->row};
        if(in_widgets())wid.count++;
        return files?((clicked&&ev.dclick)||(sel&&ev.action)): clicked;
    }