powershell - Parsing of "case" constants in Switch statements does not make sense -

can explain me behaviour of second switch statement in code:

function weird() {     $l_ret= [system.windows.forms.dialogresult]::abort     "begin switch ok"     switch( $l_ret )     {         ([system.windows.forms.dialogresult]::abort)  { 'abort'  }         ([system.windows.forms.dialogresult]::cancel) { 'cancel' }     }     "end switch ok"     "begin switch bad"     switch( $l_ret )     {         [system.windows.forms.dialogresult]::abort  { 'abort'  }         [system.windows.forms.dialogresult]::cancel { 'cancel' }     }     "end switch bad" } 

if invoke weird, get:

begin switch ok abort end switch ok begin switch bad end switch bad 

but expect is:

begin switch ok abort end switch ok begin switch bad abort end switch bad 

[edited clearer i'm asking] in other words, kind of parsing mode in when parsing case values not recognize typed enum constants???

thanks.

edit: keith's second-to-last comment in checked answer below "answer". other comments useful. thanks.

as bruce mentions, need add parens around type specifier in bad switch e.g.:

function weird() {     $l_ret= [system.windows.forms.dialogresult]::abort     "begin switch ok"     switch( $l_ret )     {         ([system.windows.forms.dialogresult]::abort)  { 'abort'  }         ([system.windows.forms.dialogresult]::cancel) { 'cancel' }     }     "end switch ok"     "begin switch bad"     switch( $l_ret )     {         ([system.windows.forms.dialogresult]::abort)  { 'abort'  }         ([system.windows.forms.dialogresult]::cancel) { 'cancel' }     }     "end switch bad" } 

otherwise powershell interprets information string , not type specifier. operates way switching on simple string tokens is, well, simple e.g.:

$var = "bar" switch ($var) {     foo { "foo" }     bar { "bar" } } 

it typical switch statements operate on literal values instead of expressions. powershell allows use expressions typically specify expressions scriptblock {...}. appears powershell accepts parens (evals expression literal match). inline powershell's command parsing mode.

fwiw note on switch bit misleading:

followed    {        "string"|number|variable|{ expression } { statementlist }        default { statementlist }    } 

this seem indicate string literals must quoted when don't need be. well, except when string contains spaces or other punctuation {, ;, etc.

btw shortened version works:

    switch( $l_ret )     {         abort  { 'abort'  }         cancel { 'cancel' }     } 

powershell knows how coerce field name of enum enum type if knows expected enum type is. unfortunate powershell can't that, @ least in case, specified name.