is_deeply($path, ['l'], '_slide_tail lit/limit path');
$r = new Regexp_Assemble();
# acids/acidoids
$path = ['d', 'i', 'c', 'a'];
$tail = ['' => 0, 'd' => ['d', 'i', 'o']];
$head = ['s'];
list($head, $slide, $path) = $r->_slide_tail($head, $tail, $path, $context);
is_deeply($head, ['s', 'd', 'i'], '_slide_tail acids/acidoids head');
is_deeply($slide, ['' => 0, 'o' => ['o', 'd', 'i']], '_slide_tail acids/acidoids slide');
is_deeply($path, ['c', 'a'], '_slide_tail acids/acidoids path');
$r = new Regexp_Assemble();
# 007/00607
$path = ['0', '0'];
$tail = ['' => 0, '0' => ['0', '6']];
$head = ['7'];
list($head, $slide, $path) = $r->_slide_tail($head, $tail, $path, $context);
is_deeply($head, ['7', '0'], '_slide_tail 007/00607 head');
is_deeply($slide, ['' => 0, '6' => ['6', '0']], '_slide_tail 007/00607 slide');
is_deeply($path, ['0'], '_slide_tail 007/00607 path');
$ra = new Regexp_Assemble();
$ra->insert('0');
$ra->insert('1');
$ra->insert('2');
$ra->_reduce();
is_deeply($ra->__path, [[0 => ['0'], 1 => ['1'], 2 => ['2']]], '/0/ /1/ /2/');
$ra = new Regexp_Assemble();
$ra->insert('c', 'a', 't')->insert('d', 'o', 'g')->insert('b', 'i', 'r', 'd')->insert('w', 'o', 'r', 'm')->_reduce();
is_deeply($ra->__path, [['b' => ['b', 'i', 'r', 'd'], 'c' => ['c', 'a', 't'], 'd' => ['d', 'o', 'g'], 'w' => ['w', 'o', 'r', 'm']]], '/cat/ /dog/ /bird/ /worm/');
$ra = new Regexp_Assemble();
$ra->insert('p', 'r', 'o', 'a', 'm', 'e', 'n', 'd', 'm', 'e', 'n', 't')->insert('p', 'r', 'o', 'a', 'p', 'p', 'r', 'o', 'p', 'r', 'i', 'a', 't', 'i', 'o', 'n')->insert('p', 'r', 'o', 'a', 'p', 'p', 'r', 'o', 'v', 'a', 'l')->_reduce();
is_deeply($ra->__path, ['p', 'r', 'o', 'a', ['m' => ['m', 'e', 'n', 'd', 'm', 'e', 'n', 't'], 'p' => ['p', 'p', 'r', 'o', ['p' => ['p', 'r', 'i', 'a', 't', 'i', 'o', 'n'], 'v' => ['v', 'a', 'l']]]]], '/proamendment/ /proappropriation/ /proapproval/');