Vim-LaTeX Feature Round Up

This is mostly an answer to a question on Vi.SE.

There are many features present in Vim-LaTeX. I don't remember all of them. I'll just talk about features that I know and use constantly.

Note: These are my limited user experience, which may be very misleading. I'm not a seasoned Vim user. And I know of nothing about vimscript.

IMAP() and <C-j> Jumpping

IMAP() function and <C-j> jumpping functions are provided separately as a plugin imaps.vim in Vim-LaTeX bundle. They are powerful features and could be very useful even when you are not writing LaTeX.

  • IMAP() function provides a more natural way to do insert mode mappings and templating in general than the built-in imap and iabbrev, IMO.

  • <C-j> jumpping is utilized by many Vim-LaTeX completion features. A jumpping point is indicated by <++>.

  • Built-in insert mode key mappings are implemented as IMAP() calls. For example, you can find a long list of useful IMAP() calls in main.vim file:

call IMAP ('__', '_{<++>}<++>', "tex")
call IMAP ('()', '(<++>)<++>', "tex")
call IMAP ('[]', '[<++>]<++>', "tex")
call IMAP ('{}', '{<++>}<++>', "tex")
...
call IMAP ('((', '\left( <++> \right)<++>', "tex")
call IMAP ('[[', '\left[ <++> \right]<++>', "tex")
call IMAP ('{ {', '\left\{ <++> \right\}<++>', "tex")
...

Then when you type say (), the cursor will reside automatically between the parenthese, replacing the first <++>. After you finished typing inside, you kick <C-j> and bang, the cursor will move out of parenthese and you just keep typing forward. Once you are used to it, it begins to form a typing flow which is kinda addictive...

You see from above a \left \right pair can be typed easily with double stroke of its opening bracket. And <C-j> jumpping makes typing flow.

One major glitch of IMAP() and <C-j> thing is that they messes up your last change history. (One bug I wish to fix for a long time.) Therefore, you may encounter unexpected behavior when trying to redo your last change by . if your "supposed last change" contains these function calls.

  • You can do all kinds of mappings using IMAP(), from simple key mappings to more complex templating. Here are some examples of my mappings (ftplugin/tex.vim):
call IMAP('*EEQ',"\\begin{equation*}\<CR><++>\<CR>\\end{equation*}<++>",'tex')
call IMAP('DEF',"\\begin{definition}[<++>]\<CR><++>\<CR>\\end{definition}<++>",'tex')
call IMAP('BIC','\binom{<++>}{<++>}<++>','tex')
call IMAP('PVERB','\PVerb{<++>}<++>','tex')
call IMAP('VERB','\verb|<++>|<++>','tex')
  • An interesting fact about imaps.vim plugin is that it's a global plugin, which implies its potential usage beyond LaTeX. Indeed, I do use <++> and <C-j> jumppings (combining with other plugins) to build code snippet templates in C.

<F5> <F7> Insertion of Commands and Environments

One disadvantage of IMAP() is that the key combination can not be used in normal text anymore (unless you undo the mapping by u). In the cases that you just want to trigger the mapping as you wish, the <F5> and <F7> come in handy. These two keys are used for triggering environments and inline commands insertion, respectively. And they behave differently based on the mode and customizations from user.

  • In Insert/Normal Mode, when the cursor is attaching a word or is in the word, pressing <F5> will by default insert a basic environment of the form
\begin{word}

\end{word}<++>

based on the word; pressing <F7> will by default insert a basic inline command of the form \word{}<++> based on the word.

  • "By default", I mean you can customize the behavior of a specific word when triggered by <F5>/<F7>. Here are some of my settings (.vimrc):
let g:Tex_Com_newcommand = "\\newcommand{<++>}[<++>]{<++>}<++>"
let g:Tex_Com_latex = "{\\LaTeX}<++>"
let g:Tex_Com_D = "\\D{<++>}{<++>}<++>"

  • In Insert/Normal Mode, when the cursor is not attached to anything (a.k.a alone), pressing <F5>/<F7> will prompt to you a menu to select environment/command to insert. Or you can type the name of desired environment/command at the bottom. Personally, I rarely use <F5>/<F7> this way.

  • Press <F5>/<F7> after visually selecting a piece of text will prompt a menu for wrapping text. Then the selected text will be wrapped in the environment/command you selected or typed.

  • In Insert/Normal Mode, when the cursor is in the scope of an environment/command, press <Shift>+<F5>/<F7> will prompt a menu for changing environment/command.

Misc Key Mappings

  • Greek Letters. `a to `z and corresponding capitals.
  • Symbols like `8 for \infty, `< for \le, `I for \int_{<++>}^{<++>}<++>, etc.
  • Pressing " twice gets a pair of normal TeX quotes. So to type literal " character, you have to use .
  • Pressing in several enumeration environments will insert appropriate \item tag.
  • You can wrap visually selected part of math in \left \right pair by `(, `[ and `{.
  • Folding is customizable. Three global variable control what can be folded: Tex_FoldedSections, Tex_FoldedMisc, and Tex_FoldedEnvironments.

Sometimes the built-in mappings have just gone too far or are not quit what you want. You can override the built-in mappings by redefining them in after/ftplugin/tex.vim:

call IMAP('`|','\abs{<++>}<++>','tex')
call IMAP('ETE',"\\begin{table}\<CR>\\centering\<CR>\\caption{<+Caption text+>}\<CR>\\label{tab:<+label+>}\<CR>\\begin{tabular}{<+dimensions+>}\<CR><++>\<CR>\\end{tabular}\<CR>\\end{table}<++>",'tex')
call IMAP('==','==','tex')
call IMAP('`\','`\','tex')

Set Multiple Compilation Engine

I always need to switch between pdflatex and xelatex engine. Thus, I have the following lines in my .vimrc:

"switch to pdflatex
function SetpdfLaTeX()
    let g:Tex_CompileRule_pdf = 'pdflatex --interaction=nonstopmode -synctex=1 -src-specials $*'
endfunction
noremap <Leader>lp :<C-U>call SetpdfLaTeX()<CR>

"switch to xelatex
function SetXeLaTeX()
    let g:Tex_CompileRule_pdf = 'xelatex --interaction=nonstopmode -synctex=1 -src-specials $*'
endfunction
noremap <Leader>lx :<C-U>call SetXeLaTeX()<CR>

View PDF, Forward and Backward Search between Vim and PDF viewer

This is a messy and complicated topic. With certain PDF viewer and a certain amount of luck, it can be very easy. But it's mainly a matter of google search.

Suggestions

  • You should find your balance between LaTeX way and Vim-LaTeX way.
  • Vim-LaTeX is no light-weight at all. There are some features and/or key mappings you'll possibly never gonna use and you have to manually override them.
  • You use Vim. You know what patience mean. :-)

Overall, I think it will work well if you are willing to invest some time to tame the beast. That being said, had I time and adequate knowledge, I will surely thin off the overhead features and explore the potentials of integration with other plugins.

References

Written on February 28, 2015