Add alignment functions and documentation.

README.mkd

@@ -40,6 +40,8 @@ Tips and useful commands
         noremap <silent><buffer> <2-LeftMouse>\
         :call ledger#transaction_state_toggle(line('.'), ' *?!')<CR>
 
+* Align commodities at the decimal point. See `help ledger-tips`.
+
 Configuration
 -------------
 

autoload/ledger.vim

@@ -330,3 +330,66 @@ function! s:findall(text, rx)
 
   return matches
 endf
+
+" Move the cursor to the specified column, filling the line with spaces if necessary.
+function! s:goto_col(pos)
+  exec "normal" a:pos . "|"
+  let diff = a:pos - virtcol('.')
+  if diff > 0 | exec "normal" diff . "a " | endif
+endf
+
+" Align the amount expression after an account name at the decimal point.
+"
+" This function moves the amount expression of a posting so that the decimal
+" separator is aligned at the column specified by g:ledger_align_at.
+"
+" For example, after selecting:
+"
+"   2015/05/09 Some Payee
+"     Expenses:Other    $120,23  ; Tags here
+"     Expenses:Something  $-4,99
+"     Expenses:More                 ($12,34 + $16,32)
+"
+"  :'<,'>call ledger#align_commodity() produces:
+"
+"   2015/05/09 Some Payee
+"      Expenses:Other                                    $120,23  ; Tags here
+"      Expenses:Something                                 $-4,99
+"      Expenses:More                                     ($12,34 + $16,32)
+"
+function! ledger#align_commodity()
+  " Extract the part of the line after the account name (excluding spaces):
+  let rhs = matchstr(getline('.'), '\m^\s\+[^;[:space:]].\{-}\(\t\|  \)\s*\zs.*$')
+  if rhs != ''
+    " Remove everything after the account name (including spaces):
+    .s/\m^\s\+[^[:space:]].\{-}\zs\(\t\|  \).*$//
+    if g:ledger_decimal_sep == ''
+      let pos = matchend(rhs, '\m\d[^[:space:]]*')
+    else
+      " Find the position of the first decimal separator:
+      let pos = match(rhs, '\V' . g:ledger_decimal_sep)
+    endif
+    " Go to the column that allows us to align the decimal separator at g:ledger_align_at:
+    call s:goto_col(g:ledger_align_at - pos - 1)
+    " Append the part of the line that was previously removed:
+    exe 'normal a' . rhs
+  endif
+endf!
+
+" Align the amount under the cursor and append/prepend the default currency.
+function! ledger#align_amount_at_cursor()
+  " Select and cut text:
+  normal viWd
+  " Find the position of the decimal separator
+  let pos = match(@", g:ledger_decimal_sep) " Returns zero when the separator is the empty string
+  " Paste text at the correct column and append/prepend default commodity:
+  if g:ledger_commodity_before
+    call s:goto_col(g:ledger_align_at - (pos > 0 ? pos : len(@"))  - len(g:ledger_default_commodity) - len(g:ledger_commodity_sep) - 1)
+    exe 'normal a' . g:ledger_default_commodity . g:ledger_commodity_sep
+    normal p
+  else
+    call s:goto_col(g:ledger_align_at - (pos > 0 ? pos : len(@")) - 1)
+    exe 'normal pa' . g:ledger_commodity_sep . g:ledger_default_commodity
+  endif
+endf!
+

doc/ledger.txt

@@ -53,6 +53,38 @@ Tips and useful commands
         noremap <silent><buffer> <2-LeftMouse>\
         :call ledger#transaction_state_toggle(line('.'), ' *?!')<CR>
 
+* `:LedgerAlign`
+
+  moves the amount expression of a posting so that the decimal separator is
+  aligned at the column specified by g:ledger_align_at. If an amount has no
+  decimal point, the imaginary decimal point to the right of the least
+  significant digit will align. The command acts on a range, with the default
+  being the current line.
+
+  The decimal separator can be set using `g:ledger_decimal_sep`. The default
+  value of `g:ledger_decimal_sep` is `'.'`.
+
+  It is convenient to remap the command, for example to `<Leader>a`:
+
+        au FileType ledger vnoremap <silent><buffer> <Leader>a \
+        :LedgerAlign<CR>
+
+* :call ledger#align_amount_at_cursor()
+
+  aligns the amount under the cursor and append/prepend the default currency.
+  The default currency can be set using `g:ledger_default_commodity`. Whether
+  the commodity should be inserted before the amount or appended to it can be
+  configured with the boolean flag `g:ledger_commodity_before` (the default
+  value is 1). A separator between the commodity and the amount may be set
+  using `g:ledger_commodity_sep`.
+
+  It is convenient to define a mapping like the following:
+
+        au FileType ledger inoremap <silent><buffer> <C-l> \
+        <Esc>:call ledger#align_amount_at_cursor()<CR>
+
+  Now, you may type `123.45<C-l>`, and have `$123.45` properly aligned (assuming
+  your default commodity is set to `'$'`).
 ==============================================================================
 SETTINGS                                                     *ledger-settings*
 
@@ -90,6 +122,26 @@ behaviour of the ledger filetype.
   folding. You can take advantage of this to disable this feature on a
   case-by-case basis.
 
+* Decimal separator:
+
+        let g:ledger_decimal_sep = '.'
+
+* Specify at which column decimal separators should be aligned:
+
+        let g:ledger_align_at = 60
+
+* Default commodity used by `ledger#align_amount_at_cursor()`:
+
+        let g:ledger_default_commodity = ''
+
+* Flag that tells whether the commodity should be prepended or appended to the
+  amount:
+
+        let g:ledger_commodity_before = 1
+
+* String to be put between the commodity and the amount:
+
+        let g:ledger_commodity_sep = ''
 ==============================================================================
 COMPLETION                                                 *ledger-completion*
 

ftplugin/ledger.vim

@@ -51,6 +51,26 @@ if !exists('g:ledger_fillstring')
   let g:ledger_fillstring = ' '
 endif
 
+if !exists('g:ledger_decimal_sep')
+  let g:ledger_decimal_sep = '.'
+endif
+
+if !exists('g:ledger_align_at')
+  let g:ledger_align_at = 60
+endif
+
+if !exists('g:ledger_default_commodity')
+  let g:ledger_default_commodity = ''
+endif
+
+if !exists('g:ledger_commodity_before')
+  let g:ledger_commodity_before = 1
+endif
+
+if !exists('g:ledger_commodity_sep')
+  let g:ledger_commodity_sep = ''
+endif
+
 " If enabled this will list the most detailed matches at the top {{{
 " of the completion list.
 " For example when you have some accounts like this:
@@ -328,3 +348,10 @@ endf "}}}
 function! s:count_expression(text, expression) "{{{2
   return len(split(a:text, a:expression, 1))-1
 endf "}}}
+
+" Commands {{{1
+if !exists(":LedgerAlign")
+  command -range LedgerAlign <line1>,<line2>call ledger#align_commodity()
+endif
+" }}}
+