i don't really understand this: in z-code thre are tasks that other competitive softwares would need to restart all over again while z-code can do it without restarting...

Machine Tags

A new kind of tags — machine tags — are supported now. A machine tag, e.g. meta:language=python consists of a namespace (meta), a key (language) and a value (python). Everyone can created machine tags, but the meta: namespace is protected and tags in there will be created by the site itself.

The codesite itself uses machine tags to make various properties of recipes accessible to the search:

• meta:language

  The programming language of the recipe, e.g. python, perl or tcl.

• meta:min_$lang_$majorver

  Those tags describe the minimum language version. If a recipe requires Python 2.5 it would have the tag meta:min_python_2=5.

• meta:license

  The license that was selected by the author, e.g. psf, mit or gpl.

• meta:loc

  This tag contains a number describing the lines of code in a recipes. It counts only the number of lines in the code block but not any lines in the discussion of in comments. This makes it possible to search for short recipes with less than ten lines or very large ones.

• meta:score

  The current score of the recipe. This is the same number that is displayed besides the recipe title and can only be influenced by voting on recipes. That way you could even search for down-voted recipes

• meta:requires

  Stores information about additional requirements of the recipes, e.g. required python modules. You can find recipes using python's collections module that way.

All those tags cannot be changed directly because they are generated from a recipe's properties.

assembly code 和 machine code 相比最大的区别是什么？