Comparing strings - is it a bug?

My computer has Hungarian regional setting, with the Hungarian default sort
order. The official Hungarian alphabet is: a á b c d e é f g ...

When I compare strings in PowerShell I receive this:

[91] PS I:\>"á" -gt "a"
True
[92] PS I:\>"áb" -gt "ab"
True
[93] PS I:\>"ác" -gt "ab"
True
[94] PS I:\>"áb" -gt "ac"
False

I don't understand the last one! If "á" is greater than "a" (that's OK),
then why "áb" is not greater than "ac"??????? Is it a bug?
--
Tibor

ASAIK, PowerShell converts the characters to their numeric values and then
compares the two. Take into count that the comparison is not case-sensitive.
Find the characters value, it may give you a hint:

([int[]][char[]]"áb" | measure-object -sum).sum

([int[]][char[]]"ac" | measure-object -sum).sum


-----
Shay Levi
$cript Fanatic
http://scriptolog.blogspot.com

The result:

[1] PS I:\>([int[]][char[]]"áb" | measure-object -sum).sum
323
[2] PS I:\>([int[]][char[]]"ac" | measure-object -sum).sum
196

Anyway, I don't think PS works the way you described... It's not that easy,
because it should take into account the different sort orders of different
cultures.

Tibor

Hi

The results from the below culture-aware script are both true on my machine,
can you check yours?

##############

$huCculture = "hu-HU"

[scriptblock] $script = {
$ab = ([int[]][char[]]"áb" | measure-object -sum).sum
$ac = ([int[]][char[]]"ac" | measure-object -sum).sum
$ab -gt $ac
"áb" -gt "ac"
}

$oldCulture = [System.Threading.Thread]::CurrentThread.CurrentUICulture

[System.Threading.Thread]::CurrentThread.CurrentUICulture = $huCculture
[System.Threading.Thread]::CurrentThread.CurrentCulture = $huCculture

& $script

[System.Threading.Thread]::CurrentThread.CurrentUICulture = $oldCulture
[System.Threading.Thread]::CurrentThread.CurrentCulture = $oldCulture

#################



-----
Shay Levi
$cript Fanatic
http://scriptolog.blogspot.com

BTW, the numeric results I get:

PS > ([int[]][char[]]"áb" | measure-object -sum).sum
1587

PS > ([int[]][char[]]"ac" | measure-object -sum).sum
196

-----
Shay Levi
$cript Fanatic
http://scriptolog.blogspot.com

My results for your script:

True
False

--
Tibor


"Shay Levi" wrote:

What are the values you get for $ab and $ac?

-----
Shay Levi
$cript Fanatic
http://scriptolog.blogspot.com

When both operands are strings PowerShell compares strings as strings, alphabetically:

# true because á's position in the alphabet is greater than a's
'á'-gt'a'

# true, same as before; the next element in both operands is the same
'áb'-gt'ab'

# true, á's position in the alphabet is greater than a's
# and so is c's position regarding b's
'ác'-gt'ab'

# false, even though á's position is greater than a's
# b's position is lower than c's; the string 'áb' comes
# before -or is less than- 'ac' when sorted alphabetically
'áb'-gt'ac'

# sorting the strings demonstrates it
'á','a' | sort
'áb','ab' | sort
'ác','ab'| sort
'áb','ac'| sort

# compare numbers as strings
# true, obviously
'13'-gt'12'

# sort numbers as strings
'13','12'|sort

# false, but 123 is greater than 13
# the thing is that they are strings not integers
'123'-gt'13'

# sort numbers as strings
'123','13'|sort

--
Kiron