As of PHP 5.1.0, the CLI SAPI provides an interactive shell using the -a option if PHP is compiled with the --with-readline option.
Using the interactive shell you are able to type PHP code and have it executed directly.
Example #1 Executing code using the interactive shell
$ php -a
Interactive shell
php > echo 5+8;
13
php > function addTwo($n)
php > {
php { return $n + 2;
php { }
php > var_dump(addtwo(2));
int(4)
php >
The interactive shell also features tab completion for functions, constants, class names, variables, static method calls and class constants.
Example #2 Tab completion
Pressing the tab key twice when there are multiple possible completions will result in a list of these completions:
php > strp[TAB][TAB] strpbrk strpos strptime php > strp
When there is only one possible completion, pressing tab once will complete the rest on the same line:
php > strpt[TAB]ime(
It is also possible doing completion on things that have been defined during the interactive shell session:
php > $fooThisIsAReallyLongVariableName = 42; php > $foo[TAB]ThisIsAReallyLongVariableName
The interactive shell stores your history and can be accessed using the up and down keys. The history is saved in the ~/.php_history file.
Note: Files included through auto_prepend_file and auto_append_file are parsed in this mode but with some restrictions - e.g. functions have to be defined before called.
Note: Autoloading is not available if using PHP in CLI interactive mode.