Need a regex for matching multiple words within parentheses

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Hello Monks! I can't figure out how to match a series of characters and spaces within two '()'.

The problem is $3. I'm trying to match the following expression.

  
$_ =~ /^ALTER\s+TABLE\s+(\w+)\s+ADD\s+CONSTRAINT\s+(\w+)\s+PRIMARY\s+K
+EY\s+\(\s*(.)\s*)/;

 $table=$1;
 $name=$2;
 $col=$3;


---DATA---
ALTER TABLE ORDERS ADD CONSTRAINT PK_ORDER_ORDER_NUM PRIMARY KEY ( ORD
+ER_NUM) ;
ALTER TABLE ORDER_ITEMS ADD CONSTRAINT PK_ORDER_NUM_ITEMS PRIMARY KEY 
+( ORDER_NUM, ITEM_NUM, SUB_TYPE ) ;
[download]

What am I doing wrong?

Comment on Need a regex for matching multiple words within parentheses Download Code

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Re: Need a regex for matching multiple words within parentheses by hanenkamp (Pilgrim) on Dec 12, 2003 at 18:42 UTC
There are a couple obvious problems. First, `(.)`. in the third match should contain a quantifier and you should be careful of "`.`" as a greedy match will swallow the end parenthesis and cause the match to fail. I'd use ~~`(\S+)` or~~ `(.+?)`. Second, you should have another backslash before the very last closing parenthesis. Note: I didn't take the time to test these recommendations. Update: Er...duh, don't do that... Update: That is, don't do the striked one, it will get the first word (or more if there is no whitespace between), but the other works fine. Sorry, I was unclear.	[reply] [d/l] [select]
Re: Re: Need a regex for matching multiple words within parentheses by Not_a_Number (Prior) on Dec 12, 2003 at 19:51 UTC
Er...duh, don't do that... Why not? Your suggestion - with `(.+?)` - works fine for me: `while ( <DATA> ) { if ( /^ALTER\s+TABLE\s+ (\w+) # $1 \s+ADD\s+CONSTRAINT\s+ (\w+) # $2 \s+PRIMARY\s+KEY\s+$\s* (.+?) # $3 \s*$/x ) { print "\$1: <$1> \$2: <$2> \$3: <$3>\n"; } } __DATA__ ALTER TABLE ORDERS ADD CONSTRAINT PK_ORDER_ORDER_NUM PRIMARY KEY ( ORD +ER_NUM) ALTER TABLE ORDER_ITEMS ADD CONSTRAINT PK_ORDER_NUM_ITEMS PRIMARY KEY +( ORDER_NUM, ITEM_NUM, SUB_TYPE )` [download] ++hanenkamp (or have I missed something?) dave	[reply] [d/l] [select]
Re: Need a regex for matching multiple words within parentheses by ysth (Canon) on Dec 12, 2003 at 18:39 UTC
() are special regex grouping characters. To match literal () characters, put a \ before them. Update: apparently I can't read a simple question. Your parens are doing just fine, but you need a +? after the . in (.)	[reply]