Description:
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I cannot declare a const a i would like to although i only use constant data.
imho a concatenation of constant strings should be possible. the same as any operation on only constant values should be allowed.
please? :-D

Reproduce code:
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class SiteConfig {
  const HOST = 'www.test.com';
  const DOC_ROOT = '/sites/aa/2484356/htdocs/';
  const WEBMASTER_MAIL = 'webmaster@test.com';
  const DEBUG = false;
}

class AppConfig {
	const HOME = SiteConfig::DOC_ROOT.'inc/lib/app/';
}

Expected result:
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AppConfig::HOME == '/sites/aa/2484356/htdocs/inc/lib/app/'

Actual result:
--------------
syntax error