Add :eval command

[tyru]

@blueyed could you review again? if you approve this, I will merge this. (cc: @mattn)

[mattn]

Codes looks okay to me. And tested this on Windows. 👍 to merge.

[mattn]

Ah, please wait merge.

[mattn]

Okay, tests passed.

It require small hacks on Windows.

diff --git a/Makefile b/Makefile
index 5074f4a..01ccc8a 100644
--- a/Makefile
+++ b/Makefile
@@ -15,7 +15,7 @@ clean_compiled:
        $(RM) $(COMPILED_FILES)

 check: all
-       git diff --exit-code $(COMPILED_FILES) || { \
+       git diff -w --exit-code $(COMPILED_FILES) || { \
          echo 'Compiled files were updated, but should have been included/committed.'; \
          exit 1; }

@@ -37,6 +37,6 @@ py/test: py/vimlparser.py

 test/node_position/test_position.out: test/node_position/test_position.vim test/node_position/test_position.ok
        vim -Nu test/vimrc -S test/node_position/test_position.vim
-       diff -u test/node_position/test_position.ok test/node_position/test_position.out
+       diff -uw test/node_position/test_position.ok test/node_position/test_position.out

 .PHONY: all clean_compiled check test fast-test vim/test js/test py/test
diff --git a/test/run.vim b/test/run.vim
index bd7c029..0e2bf2c 100644
--- a/test/run.vim
+++ b/test/run.vim
@@ -25,7 +25,7 @@ function! s:run()
     catch
       call writefile([v:exception], outfile)
     endtry
-    let diff = system(printf('diff -u %s %s', shellescape(okfile), shellescape(outfile)))
+    let diff = system(printf('diff -uw %s %s', shellescape(okfile), shellescape(outfile)))
     if empty(diff)
       let line = printf('%s => ok', fnamemodify(vimfile, ':.'))
       call append(line('$'), line)
diff --git a/test/run_command.sh b/test/run_command.sh
index 2a079d8..c165196 100755
--- a/test/run_command.sh
+++ b/test/run_command.sh
@@ -28,7 +28,7 @@ test_file() {

   ${vimlparser} ${neovim} ${vimfile} &> ${outfile}

-  diffout=$(diff -u ${outfile} ${okfile})
+  diffout=$(diff -uw ${outfile} ${okfile})
   if [ -n "$diffout" ]; then
     exit_status=1
     echo "${diffout}"

Anyway LGTM.

[tyru]

oh, CRLF... Thanks for review.