IF ... BEGIN ... END Problem

I can't see why i get this error :

Server: Msg 156, Level 15, State 1, Procedure fn_GetSpouseFrSecondPerson, Line 49
Incorrect syntax near the keyword 'BEGIN'.

from this code :

if (@flags | @LN_MATCH)
BEGIN
set @nPos = charindex(@sOwnerslast, @sSecondperson)
set @sSpouse = left(@sSecondperson, @nPos - 1)
END

(whole listing is below for the curious)

the problem is not my boolean test; if i just replace it with TRUE, the same results.

Only by commenting out the BEGIN ... END block eliminates the error.

Is there some esoteric rule about which commands or how much or how little can be in a code block?

I'm stumped...

Thanks,

Joe


SET QUOTED_IDENTIFIER ON
GO
SET ANSI_NULLS ON
GO
ALTERFUNCTION fn_GetSpouseFrSecondPerson(
@sOwnersName varchar(50),
@sSecondPerson varchar(40),
@sToken varchar(10),
@TrustFlag int, -- implicit cast from datetime does not work (how are nulls cast?)
@CompFlag int
)
RETURNS varchar(30)
AS
BEGIN

-- if SecondPerson is empty, return empty
if @sSecondPerson = '' RETURN ''
if @sSecondPerson is NULL RETURN ''

DECLARE @sOwnersLast varchar(50)
if @TrustFlag is not null SET @TrustFlag = 1 else SET @TrustFlag = 0 --convert null to 0

DECLARE @sSpouse varchar(40), @nLen int, @nPos int
DECLARE @nOwnerSex int, @nSpouseSex int

DECLARE @flags int -- store flags
SET @flags = 0 -- initialize
DECLARE @TRUST int, @COMP int, @LN_MATCH int, @FOR int, @FN_DIFF int, @HW int -- flags bitmasks
SET @TRUST= 1
SET @COMP= 2
SET @FOR= 4
SET @LN_MATCH= 8
SET @FN_DIFF= 16
SET @HW= 32

-- get last name of ownersname without suffix (JR, etc)
SET @sOwnersLast = dbo.fn_GetLastNameNoSuffix(@sOwnersName)


-- first check for spouse with same last name as ownersname

if @TrustFlag = 1 set @flags = @flags + @TRUST

if@CompFlag = 1set @flags = @flags + @COMP

if charindex('FOR', @sSecondPerson) > 0
set @flags = @flags + @FOR

if charindex(@sOwnersLast,@sSecondPerson) > 0
set @flags = @flags + @LN_MATCH

if (@flags | @LN_MATCH)
BEGIN
set @nPos = charindex(@sOwnerslast, @sSecondperson)
set @sSpouse = left(@sSecondperson, @nPos - 1)
END


SET @sSpouse = ProcsAndFuncs.dbo.fn_StrConv(@sSpouse)
RETURN @flags + ':' + @sSpouse
END--function

GO
SET QUOTED_IDENTIFIER OFF
GO
SET ANSI_NULLS ON
GO