Using start hooks

It is possible to add callbacks to Boris that are executed inside the REPL before it begins looping. Any number of hooks can be added, and they will be executed in order. Any variables set or exported by the hook will become visible from inside the REPL and consequently, to subsequent hooks that are run.

There are two ways to specify hooks: as arbitrary strings of PHP code to evaluate, or as callbacks given as closures. Both approaches allow you access to the scope, though you need to do slightly more work with the callback approach.

// this will simply be evaluated in the REPL scope
// the variables $foo and $bar will be visible inside the REPL
$boris->onStart('$foo = 42; $bar = 2; echo "Hello Boris!\n";');

// this will be passed the REPL and it's scope as arguments
// any changes to the scope can be expressed by invoking the usual
// methods on the REPL
$boris->onStart(function($worker, $scope){
  extract($scope); // we could also just access specific vars by key

  echo '$foo * $bar = ' . ($foo * $bar) . "\n";

  $worker->setLocal('name', 'Chris');
});

Above we added two hooks. The first just gets passed to eval() and leaves $foo and $bar in scope. The second uses the callback style and reads its variables from the $scope parameter, then sets variables into the REPL with setLocal().

User configuration files

If you have, things you always want to do when Boris starts, such as load useful utility functions, change the prompt or set local variable, you may create a ~/.borisrc file, which will be loaded whenever Boris starts up.

The contents of this file are just arbitrary PHP code. You are not inside the REPL itself in this file, but you have access to $boris, which is the REPL object. Here's an example ~/.borisrc that sets the prompt.

<?php

/* File: ~/.borisrc */

$boris->setPrompt('prompty> ');

Boris will also look under your current working directory for this file. If it finds one on both locations, they will both be loaded by default (not that this is customizable at the code level). If you need to execute code in the REPL itself, use hooks as documented above.

Thanks to @filp for this feature!