{"id":3931,"date":"2009-06-03T08:49:00","date_gmt":"2009-06-03T08:49:00","guid":{"rendered":"https:\/\/blogs.msdn.microsoft.com\/powershell\/2009\/06\/03\/peering-into-script-modules\/"},"modified":"2019-02-18T13:12:35","modified_gmt":"2019-02-18T20:12:35","slug":"peering-into-script-modules","status":"publish","type":"post","link":"https:\/\/devblogs.microsoft.com\/powershell\/peering-into-script-modules\/","title":{"rendered":"Peering into script modules"},"content":{"rendered":"

Sometimes it\u2019s handy to access internal elements of script modules. For instance you may be using a 3rd party module in your application and would like to see the internal state for debugging purposes.<\/p>\n

This can be accomplished with the invoke operator (&) which allows you to access a modules session state:<\/p>\n

\n

& $module {script block}<\/p>\n<\/blockquote>\n

The script block is executed in the context of the module.<\/p>\n

Create a script module that exports nothing:<\/p>\n

\n
\n
[string] $foo = "IamFoo"<\/span>

function<\/span> Hidden($zarg) {
    "$zarg was passed to me"<\/span>
}

Export-ModuleMember -Function @()
<\/p><\/blockquote><\/pre>\n
<\/div>\n<\/div>\n
Save to a file \u2018NoExport.psm1\u2019, import the module and assign to a variable:<\/p>\n
\n
PS> $m = import-module .\\NoExport.psm1 -passthru<\/pre>\n
If we try to call function \u2018Hidden\u2019 we get an error because it was not exported, but we can call it with the operator & .<\/div>\n
 <\/div>\n
\n
PS>& $m {Hidden 'bar'<\/span>}
bar was passed to me<\/pre>\n
<\/div>\n<\/p>\n
Likewise, we can also retrieve and set the module variable $foo:<\/p>\n
\n
PS>& $m {$foo}
IamFoo
PS>& $m {$script<\/span>:foo = 'NewFoo'<\/span>}
PS>& $m {$foo}
NewFoo<\/pre>\n
Note that in order to set variable foo you must use script scope.<\/div>\n
 <\/p>\n
Cheers, <\/p>\n
Nigel Sharples [MSFT]<\/p>\n","protected":false},"excerpt":{"rendered":"
Sometimes it\u2019s handy to access internal elements of script modules. For instance you may be using a 3rd party module in your application and would like to see the internal state for debugging purposes. This can be accomplished with the invoke operator (&) which allows you to access a modules session state: & $module {script […]<\/p>\n","protected":false},"author":600,"featured_media":13641,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[217,248],"class_list":["post-3931","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-powershell","tag-modules","tag-powershell"],"acf":[],"blog_post_summary":"
Sometimes it\u2019s handy to access internal elements of script modules. For instance you may be using a 3rd party module in your application and would like to see the internal state for debugging purposes. This can be accomplished with the invoke operator (&) which allows you to access a modules session state: & $module {script […]<\/p>\n","_links":{"self":[{"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/posts\/3931","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/users\/600"}],"replies":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/comments?post=3931"}],"version-history":[{"count":0,"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/posts\/3931\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/media\/13641"}],"wp:attachment":[{"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/media?parent=3931"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/categories?post=3931"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/tags?post=3931"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}