function apply(TokenStream $ts, Directives $directives, BlueContext $blueContext)
{
$from = $ts->index();
$crossover = $this->pattern->match($ts);
if (null === $crossover || $crossover instanceof Error) {
return;
}
if ($this->hasExpansion) {
$blueMacros = $this->getAllBlueMacrosFromCrossover($crossover->all(), $blueContext);
if ($this->terminal && isset($blueMacros[$this->id])) {
// already expanded
$ts->jump($from);
return;
}
$ts->unskip(...TokenStream::SKIPPABLE);
$to = $ts->index();
$ts->extract($from, $to);
$expansion = $this->expansion->expand($crossover, $this->cycle, $directives, $blueContext);
$blueMacros[$this->id] = true;
// paint blue context with tokens from expansion and disabled macros
$node = $expansion->index();
while ($node instanceof Node) {
$blueContext->addDisabledMacros($node->token, $blueMacros);
$node = $node->next;
}
$ts->inject($expansion);
} else {
$ts->unskip(...TokenStream::SKIPPABLE);
$ts->skip(T_WHITESPACE);
$to = $ts->index();
$ts->extract($from, $to);
}
$this->cycle->next();
}
function hygienize(TokenStream $ts, array $context) : TokenStream
{
$ts->reset();
$cg = (object) ['node' => null, 'context' => $context, 'ts' => $ts];
$saveNode = function (Parser $parser) use($cg) {
return midrule(function ($ts) use($cg, $parser) {
$cg->node = $ts->index();
return $parser->parse($ts);
});
};
traverse(chain(token(T_STRING, '··unsafe'), either(parentheses(), braces())), either($saveNode(token(T_VARIABLE)), chain($saveNode(identifier()), token(':')), chain(token(T_GOTO), $saveNode(identifier())))->onCommit(function (Ast $result) use($cg) {
if (($t = $cg->node->token) && ($value = (string) $t) !== '$this') {
$cg->node->token = new Token($t->type(), "{$value}·{$cg->context['scope']}", $t->line());
}
}))->parse($ts);
$ts->reset();
return $ts;
}
function apply(TokenStream $ts)
{
$from = $ts->index();
$crossover = $this->pattern->parse($ts);
if (null === $crossover || $crossover instanceof Error) {
return;
}
if ($this->expansion) {
// infer blue context from matched tokens
$context = new BlueContext();
$tokens = $crossover->all();
array_walk_recursive($tokens, function (Token $token) use($context) {
$context->inherit($token->context());
});
if (!$this->hasTag('·recursion')) {
if ($context->contains($this->id())) {
return;
}
}
// already expanded
$context->add($this->id());
$ts->unskip(...TokenStream::SKIPPABLE);
$to = $ts->index();
$ts->extract($from, $to);
$expansion = $this->mutate($this->expansion, $crossover);
$this->cycle->next();
// paint blue context of expasion tokens
$expansion->each(function (Token $token) use($context) {
$token->context()->inherit($context);
});
$ts->inject($expansion, $from);
} else {
$ts->unskip(...TokenStream::SKIPPABLE);
$ts->skip(T_WHITESPACE);
$to = $ts->index();
$ts->extract($from, $to);
}
}
