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    Lists the Windows PowerShell operators in precedence order. 
    [This topic was contributed by Kirk Munro, a Windows PowerShell MVP 
     from Ottawa, Ontario]      


    Windows PowerShell operators let you construct simple, but powerful 
    expressions. This topic lists the operators in precedence order.  
    Precedence order is the order in which Windows PowerShell evaluates 
    the operators when multiple operators appear in the same expression. 
    When operators have equal precedence, Windows PowerShell evaluates  
    them from left to right. The exceptions are the assignment operators, 
    the cast operators, and the negation operators (!, -not, -bnot),  
    which are evaluated from right to left. 
    You can use enclosures, such as parentheses, to override the  
    standard precedence order and force Windows PowerShell to evaluate 
    the enclosed part of an expression before an unenclosed part.  
    In the following list, operators are listed in the order that they 
    are evaluated. Operators on the same line, or in the same group, have 
    equal precedence.  
    The Operator column lists the operators. The Reference column lists 
    the Windows PowerShell Help topic in which the operator is described. 
    To display the topic, type "get-help <topic-name>". 
    OPERATOR                         REFERENCE  
    --------                         --------- 
    $()  @()                         about_Operators 
    . (dereference) :: (static)      about_Operators 
    [0] (index operator)             about_Operators 
    [int] (cast operators)           about_Operators 
    -split (unary) -join (unary)     about_Split, about_Join 
    , (comma operator)               about_Operators 
    ++ --                            about_Assignment_Operators 
    -not ! -bNot                     about_Logical_Operators, about_Comparison_Operators 
    .. (range operator)              about_Operators 
    -f (format operator)             about_Operators  
    * / %                            about_Arithmetic_Operators 
    + -                              about_Arithmetic_Operators 
    The following group of operators have equal precedence. Their 
    case-sensitive and explicitly case-insensitive variants have 
    the same precedence. 
    -split (binary)                  about_Split 
    -join (binary)                   about_Join 
    -is  -isnot  -as                 about_Type_Operators 
    -eq  -ne  -gt  -gt  -lt  -le     about_Comparison_Operators 
    -like  -notlike                  about_comparison_operators 
    -match  -notmatch                about_comparison_operators 
    -in -notIn                       about_comparison_operators 
    -contains -notContains           about_comparison_operators 
    -replace                         about_comparison_operators 
    The list resumes here with the following operators in precedence 
    -band -bor -bxor                 about_Comparison_Operators 
    -and -or -xor                    about_Comparison_Operators 
    . (dot-source)  & (call)         about_Scopes, about_Operators 
    | (pipeline operator)            about_Operators 
    >  >>  2>  2>>  2>&1             about_Redirection 
    =  +=  -=  *=  /= %=             about_Assignment_Operators 


    The following two commands show the arithmetic operators and 
    the effect of using parentheses to force Windows PowerShell to 
    evaluate the enclosed part of the expression first. 
        C:\PS> 2 + 3 * 4 
        C:\PS> (2 + 3) * 4 
    The following example gets the read-only text files from the local 
    directory and saves them in the $read_only variable. 
        $read_only = get-childitem *.txt | where-object {$_.isReadOnly} 
    It is equivalent to the following example. 
        $read_only = ( get-childitem *.txt | where-object {$_.isReadOnly} ) 
    Because the pipeline operator (|) has a higher precedence than the 
    assignment operator (=), the files that the Get-ChildItem cmdlet  
    gets are sent to the Where-Object cmdlet for filtering before they 
    are assigned to the $read_only variable.  
    The following example demonstrates that the index operator takes 
    precedence over the cast operator. 
    The first expression creates an array of three strings. Then, it 
    uses the index operator with a value of 0 to select the first object 
    in the array, which is the first string. Finally, it casts the  
    selected object as a string. In this case, the cast has no effect. 
        C:\PS> [string]@('Windows','PowerShell','2.0')[0] 
    The second expression uses parentheses to force the cast operation 
    to occur before the index selection. As a result, the entire array 
    is cast as a (single) string. Then, the index operator selects 
    the first item in the string array, which is the first character. 
        C:\PS> ([string]@('Windows','PowerShell','2.0'))[0] 
    In the following example, because the -gt (greater-than) operator 
    has a higher precedence than the -and (logical AND) operator, the 
    result of the expression is FALSE. 
        C:\PS> 2 -gt 4 -and 1 
    It is equivalent to the following expression. 
        C:\PS> (2 -gt 4) -and 1 
    If the -and operator had higher precedence, the answer would be TRUE. 
        C:\PS> 2 -gt (4 -and 1) 
    However, this example demonstrates an important principle of managing 
    operator precedence. When an expression is difficult for people to 
    interpret, use parentheses to force the evaluation order, even when it 
    forces the default operator precedence. The parentheses make your 
    intentions clear to people who are reading and maintaining your scripts.