BUG: calculating formula for length in dialog 'Point at distance and angle' crashes

[0f22fd5950630]

• Describe the bug
  After entering two times the minus symbol the program crashes
• How To Reproduce the bug
  start Seamly2D, create a new piece, klick the button for 'Point at distance and angle' and type the minus key twice after the value for the length
• What should have happened
  '6-' should give the same 'error' value as '6--'
• console output after typing '6-'
  DEBUG: Code: 2 ( "Unexpected end of expression at position 3" )
• console output after typing the second '-'
  Segmentation fault (core dumped)
• What's your Desktop OS?
  Ubuntu 22.04.1 LTS
• What's your Seamly version from Help/About?
  

[DSCaskey]

Confirmed. I have a fix. Will make a PR sometime later this afternoon.