The function to show current file’s full path in mini buffer

TL;DR

:let @" = expand("%")>

this will copy the file name to the unamed register, then you can use good old p to paste it. and of course you can map this to a key for quicker use.

:nmap cp :let @" = expand("%")<cr>

you can also use this for full path

:let @" = expand("%:p")

Explanation

Vim uses the unnamed register to store text that has been deleted or copied (yanked), likewise when you paste it reads the text from this register.

Using let we can manually store text in the register using :let @" = "text" but we can also store the result of an expression.

In the above example we use the function expand which expands wildcards and keywords. in our example we use expand('%') to expand the current file name. We can modify it as expand('%:p') for the full file name.

See :help let :help expand :help registers for details

Folding is generally unnecessary with emacs, as it has tools that explicitly implement the actions people do manually when folding code.

Most people have good success with simple incremental searches. See "foo" mentioned somewhere? Type C-sfoo, find the definition, press enter, read it, and then press C-x C-x to go back to where you were. Simple and very useful.

Most modes support imenu. M-ximenu will let you jump to a function definition (etc.) by name. You can also bind it to a mouse click to get a menu of functions (or add it to the menubar; see the Info page for more detail). It provides data for which-function-mode, which will let you see which function you are currently inside in the modeline. (Why are your functions this long, though?)

There is also speedbar, which displays the imenu information (and other things) graphically.

If you want to get an overview of your file, try M-xoccur". Given a regex, it will create a new buffer with each match in the current buffer. You can search for "(defun" to get an overview of the functions the current file implements. Clicking on the result will move you to that position in the file.

So anyway, think about what you really want to achieve, and Emacs probably implements that. Don't fight with imperfect tools that make you fold and unfold things constantly.