syntax error for extra semicolon

[mahrud]

I did not expect this:

i1 : f = x -> x;

i2 : f = x -> x;;
stdio:2:11:(3): error: syntax error at ';'

Why are two semicolons an error?

i7 : ;;
stdio:7:0:(3): error: syntax error at ';'

[d-torrance]

Even just one by itself is:

i1 : ;
stdio:1:0:(3): error: syntax error at ';'