new README example

README.md

@@ -10,12 +10,18 @@ A very cool language
 
 ## Syntax
 ```rust
-func fib[n: I64] : I64
-    if n <= 1
-        return n
-    return fib(n-2) + fib(n-1)
-
 func main[] : I64
-    for i in 0..20
-        fib(i) |> str.from_i64() |> io.print()
+    let answer: I64 = math.abs(math.urandom()) % 100
+
+    while true
+        io.print("Guess a number: ")
+        let guess: I64 = io.read_stdin() |> str.trim() |> str.parse_i64()
+
+        if guess == answer
+            io.print("You win!")
+            break
+        else if guess < answer
+            io.print("Too low!")
+        else
+            io.print("Too high!")
 ```

src/std.zr

@@ -183,7 +183,7 @@ func str.hex_encode[s: String] : String
     str.set(out, j, 0)
     return out
 
-func str.from_hex_digit[d: U8] : I64
+func str._from_hex_digit[d: U8] : I64
     if d >= 'a' & d <= 'f'
         return d - 'a' + 10
     if d >= 'A' & d <= 'F'
@@ -197,7 +197,7 @@ func str.hex_decode[s: String] : String
     let out: String = mem.alloc(s_len/2+1)
 
     while i < s_len
-        str.set(out, j, str.from_hex_digit(str.nth(s, i)) * 16 + str.from_hex_digit(str.nth(s, i+1)))
+        str.set(out, j, str._from_hex_digit(str.nth(s, i)) * 16 + str._from_hex_digit(str.nth(s, i+1)))
         i = i + 2
         j = j + 1