This table lists the filters in CQL as well as parameters or keywords each filter uses. This table is not normative: consult the documentation for the filter for the normative definition.

This table does not include symbolic filters: ――, ., _, :, &, <, >, >=, ∊, =, =?, ==, !=, ∩, +, *, %, /, -, ~, |, {}, #, +=, -=, /=, *=, %=, ~~, [], ∪. For unicode symbols, see unicode symbols.

Deprecated filters are crossed out.

Table of Filters

Name	parameters	arguments	example
A			A==2
a			a==2
abs		number	abs #A - #a
ancestor		(position position)	ancestor(source target)
and		filter/filter	check and Q==2
ascii		string or number	X=ascii "A" Y=ascii 65
assert		filter	assert X==0
atomic variables		variable	atomic X=1
attackedby		set/set	_ attackedby k
attacks		set/set	A attacks k
B			B==2
b			b==2
between		(set set)	between(R k)
black			black
btm			btm
castle			castle
check			check
child		(number)	child(3)
child			child
colortype		set	colortype d4
comment		(filter...)	comment("x is" x)
connectedpawns			connectedpawns
consecutivemoves	range quiet	(position position)	consecutivemoves(source target)
countmoves		―― filter legal ―― filter pseudolegal ―― filter	countmoves legal ♔――
currentmove filter		―― filter	not currentmove ――=△
currentposition			currentposition
currenttransform			currenttransform
dark		set	dark B
date	implicit search parameter		date~~"199[5-9]"
depth			depth>4
descendant		(position position)	descendant(source target)
dictionary			dictionary X["a"]="bc"
distance		(position position)	distance(source target)
doubledpawns			doubledpawns>= 4
down	range	set	down P
echo	in all echo quiet	(variable variable)	echo(s t)s&t==.
eco	implicit search parameter		X=eco
elo	white black		elo>2700
event	implicit search parameter		x=event
eventdate	implicit search parameter		eventdate~~"199[4-7]"
false			false
fen	string		X=fen
file		set	file K
find	range all quiet <--	filter	find check find all check
flip	count	filter	flip Ad4 attacks k
flipcolor	count	filter	flipcolor A attacks k
fliphorizontal	count	filter	fliphorizontal Ae1 attacks k
flipvertical	count	filter	flipvertical Ae1 attacks k
from			x=from
function		{filter}	function square(x) {x * x}
gamenumber			gamenumber==1000
hascomment		string	hascomment "good" (deprecated)
Heijden database VI interface	see documentation		hhdb composer "Reti" hhdb sort award
idealmate			idealmate
idealstalemate			idealstalemate
if		testfilter consequent	if check "In check"
if		testfilter consequent else elsefilter	if check "In check" else "safe"
in		set/set	R in (A attacks k)
in		string/string	"Q" in fen
indexof		string string	indexof("King" "a King")==2
initial			initial
initialposition			initialposition:check
int		string	int "64" == 64
isbound			isbound Foo
isolatedpawns			isolatedpawns>3
isunbound			isunbound Foo
K			K attacks n
k			k attacks n
lastgamenumber			gamenumber==lastgamenumber
lca		(position position)	lca(source target)
legal		―― filter	legal ♔――a-h4
left	range	set	left P
pseudolegal		―― filter	pseudolegal ♔――a-h4
light		set	light B==2
line		filter	line-->move promote A-->mate
local		dictionary	local dictionary D
loop		filter	loop {child(i) i+=1}
lowercase		string	lowercase "Tal"=="tal"
mainline			mainline
makesquare		(number number)	makesquare(File Rank)
mate			mate
max		(number number)	max(#R #Q)
message	message quiet	(filter...)	message("x is " x)
min		(number number)	min(#R #Q)
modelmate			modelmate
modelstalemate			modelstalemate
move			move from K to _
movenumber			movenumber>100
N			N==2
n			n==2
northeast	range	set	northeast P
northwest	range	set	northwest P
not		filter	not mate
notransform		filter	notransform a4
nullmove			nullmove
o-o			o-o
o-o-o			o-o-o
or		filter/filter	check or stalemate
originalcomment		string	originalcomment "good"
P			P==2
p			p==2
parent			parent:check
passedpawns			passedpawns>= 6
⊢ / path	primary focus (or ◎) max verbose keepallbest title piecepath quiet nestban firstmatch lastposition	various	path -- check +
pathcount			pathcount
pathcountunfocused			pathcountunfocused
pathlastposition			pathlastposition
pathstatus			pathstart
persistent	quiet	variable=number	persistent x=5
piece	in all	filter	piece x in A x attacks k
piecename		set	piecename d4
piece assignment		variable=set	piece x = K
pieceid		set	pieceid x
pin	from through to		pin from Q
player player white player black	implicit search parameter		player "Kasparov" player white ~~ "Kas.*ov" x=player black
ply			ply>100
position		number	position 0
positionid			positionid == 0
power		set	power A<5
primary			primary
pseudolegal		―― filter	pseudolegal ♔――a-h4
puremate			puremate
purestalemate			purestalemate
Q			Q==2
q			q==2
R			R==2
r			r==2
rank		set	rank K == rank k
ray	direction	(set...)	ray (R a k)
readfile		string	X=readfile "a.cqo"
removecomment			removecomment
result		string	result "1-0"
reversecolor	count	filter	reversecolor A attacks k
right	range	set	right P
rotate45	count	filter	rotate45 A attacks right k
rotate90	count	filter	rotate90 A attacks up k
secondary			secondary
settag		(quoted string string or int)	settag("MyTag" "blunder")
shift	count	filter	shift A e1 attacks kg1
shifthorizontal	count	filter	shifthorizontal Ae1 attacks kg1
shiftvertical	count	filter	shiftvertical Ae1 attacks kg1
sidetomove			sidetomove==white
site	implicit search parameter		site "Berlin" x=site
sort	min documentation	number or set	sort "Material" power A
sqrt		number	sqrt 10000
square	in all	filter	square s in _ k attacks s
stalemate			stalemate
str		(filter...)	X=str("K on: " K)
tag		quoted string	tag "UTCDate"
terminal			terminal
to			y=to
true			true
try			try
type		set	type d4
typename		set	typename d4
unbind		variable dictionary dictionary[string]	unbind X unbind Dict["ch"]
up	range	set	up P
uppercase		string	uppercase "tal"=="TAL"
variation			variation
virtualmainline			virtualmainline
while: standard form	(test)body		while(x<3){z+=1 x+=1}
while: ~~ form	(target~~pattern)body		while(player~~".")...
white			white
writefile		(filename contents)	writefile("a.cqo" fen)
wtm			wtm
xray		(set...)	xray(R a k)
year			year>2000