diff --git a/DesignNotes.wiki b/DesignNotes.md similarity index 97% rename from DesignNotes.wiki rename to DesignNotes.md index a9f5662..5e7f957 100644 --- a/DesignNotes.wiki +++ b/DesignNotes.md @@ -1,10 +1,10 @@ -= Design Notes = +# Design Notes This file is meant to document design decisions and algorithms inside vimwiki which are too large for code comments, and not necessarily interesting to users. Please create a new section to document each behavior. -== Formatting tables == +## Formatting tables In vimwiki, formatting tables occurs dynamically, when navigating between cells and adding new rows in a table in the Insert mode, or statically, when pressing @@ -14,16 +14,16 @@ leaving Insert mode, provided variable `g:vimwiki_table_auto_fmt` is set. In this section, the original and the newer optimized algorithms of table formatting will be described and compared. -=== The older table formatting algorithm and why this is not optimal === +### The older table formatting algorithm and why this is not optimal Let's consider a simple example. Open a new file, say _tmp.wiki_, and create a new table with command `VimwikiTable`. This should create a blank table. -{{{ +``` | | | | | | |---|---|---|---|---| | | | | | | -}}} +``` Let's put the cursor in the first header column of the table, enter the Insert mode and type a name, say _Col1_. Then press _Tab_: the cursor will move to the @@ -31,11 +31,11 @@ second column of the header and the table will get aligned (in the context of the table formatting story, words _aligned_ and _formatted_ are considered as synonyms). Now the table looks as in the following snippet. -{{{ +``` | Col1 | | | | | |------|---|---|---|---| | | | | | | -}}} +``` Then, when moving cursor to the first data row (i.e. to the third line of the table below the separator line) and typing anything here and there while @@ -43,34 +43,34 @@ navigating using _Tab_ or _Enter_ (pressing this creates a new row below the current row), the table shall keep formatting. Below is a result of such a random edit. -{{{ +``` | Col1 | | | | | |------|-------|---|-------|----------| | | Data1 | | Data2 | | | | | | | New data | -}}} +``` The lowest row gets aligned when leaving the Insert mode. Let's copy _Data1_ (using `viwy` or another keystroke) and paste it (using `p`) in the second data row of the first column. Now the table looks mis-aligned (as we did not enter the Insert mode). -{{{ +``` | Col1 | | | | | |------|-------|---|-------|----------| | | Data1 | | Data2 | | | Data1 | | | | New data | -}}} +``` This is not a big problem though, because we can put the cursor at _any_ place in the table and press `gqq`: the table will get aligned. -{{{ +``` | Col1 | | | | | |-------|-------|---|-------|----------| | | Data1 | | Data2 | | | Data1 | | | | New data | -}}} +``` Now let's make real problems! Move the cursor to the lowest row and copy it with `yy`. Then 500-fold paste it with `500p`. Now the table very long. Move @@ -83,7 +83,7 @@ time _Tab_ or _Enter_ get pressed down, all rows in the table get visited to calculate a new alignment. Moreover, by design it may happen even more than once per one press! -{{{vim +```vim function! s:kbd_create_new_row(cols, goto_first) let cmd = "\o".s:create_empty_row(a:cols) let cmd .= "\:call vimwiki#tbl#format(line('.'))\" @@ -98,7 +98,7 @@ function! s:kbd_create_new_row(cols, goto_first) return cmd endfunction -}}} +``` Function `s:kbd_create_new_row()` is called when _Tab_ or _Enter_ get pressed. Formatting of the whole table happens in function `vimwiki#tbl#format()`. But @@ -107,25 +107,25 @@ variable `g:vimwiki_table_auto_fmt` is set. This means that formatting of the whole table is called on all those multiple interleaves between the Insert and the Normal mode in `s:kbd_create_new_row` (notice `\`, `o`, etc.). -=== The newer table formating algorithm === +### The newer table formating algorithm The newer algorithm was introduced to struggle against performance issues when formatting large tables. Let's take the table from the previous example in an intermediate state. -{{{ +``` | Col1 | | | | | |------|-------|---|-------|----------| | | Data1 | | Data2 | | | Data1 | | | | New data | -}}} +``` Then move the cursor to the first data row, copy it with `yy`, go down to the mis-aligned line, and press `5p`. Now we have a slightly bigger mis-aligned table. -{{{ +``` | Col1 | | | | | |------|-------|---|-------|----------| | | Data1 | | Data2 | | @@ -135,14 +135,14 @@ table. | | Data1 | | Data2 | | | | Data1 | | Data2 | | | | Data1 | | Data2 | | -}}} +``` Go down to the lowest, the 7th, data row and press `gq1`. Nothing happened. Let's go to the second or the third data row and press `gq1` once again. Now the table gets aligned. Let's undo formatting with `u`, go to the fourth row, and press `gq1`. Now the table should look like in the following snippet. -{{{ +``` | Col1 | | | | | |------|-------|---|-------|----------| | | Data1 | | Data2 | | @@ -152,7 +152,7 @@ and press `gq1`. Now the table should look like in the following snippet. | | Data1 | | Data2 | | | | Data1 | | Data2 | | | | Data1 | | Data2 | | -}}} +``` What a peculiar command! Does using it make any sense? Not much, honestly. Except it shows how the newer optimized table formatting algorithm works in the @@ -184,4 +184,3 @@ viewport) until one of the being edited cells grows in length to a value big enough to trigger the older algorithm and the whole table gets aligned. When partial formatting is not desirable, the whole table can be formatted by pressing `gqq` in the Normal mode. -