Please add a "Join Lines" function to the Qt Creator text editor. It should work like "J" does in vi, or like "Tools-->Join Lines (Ctrl+J)" does in KWrite, which is like this:

• let N be the current line (where the cursor is located).
• any whitespace at the end of line N is replaced by a single space character.
• any whitespace at the beginning line (N+1) is removed.
• line (N+1) is cut and then pasted at the end of line N.
• The cursor position remains the same.

For example (I'm using . instead of space characters here to make them more visible):

..abc..
..def.

becomes

..abc.def.