PHP Parse Error on namespace

[dustinpaluch]

wp> namespace dustinpaluch { }
PHP Parse error:  syntax error, unexpected 'dustinpaluch' (T_STRING), expecting \\ (T_NS_SEPARATOR) in phar:///usr/local/bin/wp/vendor/wp-cli/shell-command/src/WP_CLI/REPL.php(37) : eval()'d code on line 1

I'm trying to reproduce a bug involving namespaces, wp actions, and anonymous functions, and was hoping I'd be able to use the wp shell to make a minimal test case.

[schlessera]

The default REPL uses PHP eval() to execute the code, and eval() does not work properly with namespaces, a limitation in PHP itself.

If you want to use namespaces in wp shell, you install the additional PsySH REPL, which provides many improvements, one of them being support for namespaces.

One easy way to do so is through the package manager:

wp package install schlessera/wp-cli-psysh

[dustinpaluch]

Shouldn't this fail then, from php --interactive?

php > eval('namespace dustinpaluch { function foobar() { echo __FUNCTION__; } foobar(); }');
dustinpaluch\foobar

Looks like my code doesn't work in 5.2.x, but starts working in 5.3.x.