doc/ref/spec.md: fix int_lit `0`
Change-Id: If6dab6f595b4fac406ff6af191fbcc8eccbc5328
Reviewed-on: https://cue-review.googlesource.com/c/cue/+/8842
Reviewed-by: Marcel van Lohuizen <mpvl@golang.org>
Reviewed-by: CUE cueckoo <cueckoo@gmail.com>
diff --git a/doc/ref/spec.md b/doc/ref/spec.md
index e46add0..7fd5f5e 100644
--- a/doc/ref/spec.md
+++ b/doc/ref/spec.md
@@ -285,7 +285,7 @@
```
int_lit = decimal_lit | si_lit | octal_lit | binary_lit | hex_lit .
-decimal_lit = ( "1" … "9" ) { [ "_" ] decimal_digit } .
+decimal_lit = "0" | ( "1" … "9" ) { [ "_" ] decimal_digit } .
decimals = decimal_digit { [ "_" ] decimal_digit } .
si_it = decimals [ "." decimals ] multiplier |
"." decimals multiplier .
