<div dir="ltr"><div class="gmail_default" style="font-family:georgia,serif;font-size:small;color:#330000">DT 1.9.2</div><div class="gmail_default" style="font-family:georgia,serif;font-size:small;color:#330000"><br></div><div class="gmail_default" style="font-size:small;color:rgb(51,0,0)">
<font face="courier new, monospace">t1 <- data.table(a=1:2,b=0:1,key="a")</font></div><div class="gmail_default" style="font-size:small;color:rgb(51,0,0)"><font face="courier new, monospace"><br></font></div>
<div class="gmail_default" style="font-size:small;color:rgb(51,0,0)"><font face="courier new, monospace">t1[b==0] => row 1, OK</font></div><div class="gmail_default" style="font-size:small;color:rgb(51,0,0)"><font face="courier new, monospace">t1[!b] => ERROR "object 'b' not found" ??</font></div>
<div class="gmail_default" style="font-size:small;color:rgb(51,0,0)"><font face="courier new, monospace">t1[(!b)] => row 1, OK</font></div><div class="gmail_default" style="font-family:georgia,serif;font-size:small;color:#330000">
<br></div><div class="gmail_default" style="font-family:georgia,serif;font-size:small;color:#330000">Shouldn't !b be equivalent to (!b)? They are both expressions, not symbols.</div><div class="gmail_default" style="font-family:georgia,serif;font-size:small;color:#330000">
<br></div><div class="gmail_default" style="font-family:georgia,serif;font-size:small;color:#330000"> -s</div></div>