Parse error on .5e5

[yorickvP]

Description

The parser doesn't accept floats starting with .

Small example input

.5e5

Expected output

0.5e5

Actual output

<stdin>:1:6:
  |
1 | .0e+0
  |      ^
unexpected end of input
expecting expression

[yorickvP]

nix-repl> let e="e";in[001.2e01e.30.4]
[ 1 2 "e" 0.3 0.4 ]