2 improved formatting of markdown
source | link

Julia, 362

s = chomp(readline(STDIN))
l=""
z=" of beer"
q,r,w,t=" bottles$z"," bottle$z"," on the wall.\n","take one down, pass it around,\n"
for j=99:-1:2
b="$j$q"
l*="$b$w$b.\n$t"
end
l*="1$r$(w)1$r.\n$(t)No$q$w"
p=println
all(c->c in "HQ9+", s)||p("Source code contains invalid characters")
for c in s
    c=='Q'&&p(s)
    c=='H'&&p("Hello, world!")
    c=='9'&&p(l)
end

Julia, 362

s = chomp(readline(STDIN))
l=""
z=" of beer"
q,r,w,t=" bottles$z"," bottle$z"," on the wall.\n","take one down, pass it around,\n"
for j=99:-1:2
b="$j$q"
l*="$b$w$b.\n$t"
end
l*="1$r$(w)1$r.\n$(t)No$q$w"
p=println
all(c->c in "HQ9+", s)||p("Source code contains invalid characters")
for c in s
    c=='Q'&&p(s)
    c=='H'&&p("Hello, world!")
    c=='9'&&p(l)
end

Julia, 362

s = chomp(readline(STDIN))
l=""
z=" of beer"
q,r,w,t=" bottles$z"," bottle$z"," on the wall.\n","take one down, pass it around,\n"
for j=99:-1:2
b="$j$q"
l*="$b$w$b.\n$t"
end
l*="1$r$(w)1$r.\n$(t)No$q$w"
p=println
all(c->c in "HQ9+", s)||p("Source code contains invalid characters")
for c in s
    c=='Q'&&p(s)
    c=='H'&&p("Hello, world!")
    c=='9'&&p(l)
end
1
source | link

Julia, 362

s = chomp(readline(STDIN))
l=""
z=" of beer"
q,r,w,t=" bottles$z"," bottle$z"," on the wall.\n","take one down, pass it around,\n"
for j=99:-1:2
b="$j$q"
l*="$b$w$b.\n$t"
end
l*="1$r$(w)1$r.\n$(t)No$q$w"
p=println
all(c->c in "HQ9+", s)||p("Source code contains invalid characters")
for c in s
    c=='Q'&&p(s)
    c=='H'&&p("Hello, world!")
    c=='9'&&p(l)
end