print 'this' . ' ' x $spaces . 'that';

[download]
This would function unchanged. Someone else made an erroneous statement about 'x' having higher precedence. It doesn't. It has the same as '*', '/', and '%'. I'm saying -- combine your integers first. So above -- without the need for parents, you can write your 2nd example in 1 statement: 
print 'this' . ' ' x $n * rand() + theNumberYouFirstThoughOf() . that'
+;

[download]

You can't do the above in 1 statement in perl, 'now', but you could if you bumped the **non-combining** string operations down 1 precendence level so you can evaluate the complete numeric expression, and use that as input to your 'x' operand which needs an integer on it's right side. Same holds true for '.' at same precedence as '+' and '-'. 

perl -we'
print +2-2 . '*' . 2-2 .'='. -4+4-4+4 . '=' 0; 
'
#current perl:
Argument "0*2" isn't numeric in subtraction (-) at -e line 2.
Argument "-2=-4" isn't numeric in addition (+) at -e line 2.
2=0
# proposed would give the integer ops higher precedence and get them
out of the way of the string-combining parts.  Thus:

perl -we'
print +(2-2) . "*". (2-2) . "=" . (-4+4-4+4) . "=". 0 ."\n";
'

0*0=0=0

[download]
Thus showing the benefit and effect of proper precedence and evaluating the integer ops at higher precedence than the string ops.
∎ (Q.E.D.)?
;-)

In reply to Re^2: Precedence design question...'x' & arith by perl-diddler
in thread Precedence design question...'x' & arith by perl-diddler

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