bslNumber.nodejs

/*
    Copyright © 2011, 2012 MLstate

    This file is part of Opa.

    Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

/////////////////////////////////////////////////////////////////////////////
// NO LONGER SHARED BETWEEN NODE BSL AND JS BSL DUE TO FLOAT_PARSER IMPORT //
/////////////////////////////////////////////////////////////////////////////

##extern-type int32
##extern-type int64
##opa-type outcome('a, 'b)

// We should really use "const" here but it's not cross-browser compatible.
// Is it ok to use const in server-side only code?
// What about function myconst() { return "const"; }
var POW2_32 = 0x0000000100000000; //  2^32
var IMIN32 = -0x0000000100000000; // -2^32
var IMAX32 =  0x00000000ffffffff; //  2^32-1
var POW2_52 = 0x0010000000000000; //  2^52
var IMIN52 = -0x0010000000000000; // -2^52
var IMAX52 =  0x000fffffffffffff; //  2^52-1
var POW2_53 = 0x0020000000000000; //  2^53
var IMIN53 = -0x0020000000000000; // -2^53
var IMAX53 =  0x001fffffffffffff; //  2^53-1
var qNaNstr_be = "\x7f\xc0\x00\x00\x00\x00\x00\x00"; // quiet NaN with no payload
var qNaNstr_le = "\x00\x00\x00\x00\x00\x00\xc0\x7f";
function qNaNstr(le) { return (le) ? qNaNstr_le : qNaNstr_be; }
var qNaNarray_be = [0x7f, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]; // quiet NaN with no payload as an array
var qNaNarray_le = [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xc0, 0x7f];
function qNaNarray(le) { return (le) ? qNaNarray_le : qNaNarray_be; }

##module Int \ bsl_int

// Note: for bitwise ops you only get 32 bits - and they're sign extended
##register max_int \ max_int: int
var max_int = Math.pow(2, 53);

##register [pure] of_string : string -> int
  ##args(str)
  {
      if (str.length < 2)
          return parseInt(str,10);
      else {
          var hex = /^0x/;
          var is_hex = str.match(hex);
          if (is_hex != null)
              return parseInt(str,16);
          else {
              var oct = /^0o/;
              var is_oct = str.match(oct);
              if (is_oct != null) {
                  return parseInt(str,8);
                }
              else
                  return parseInt(str,10)
          }
      }
  }

##register [pure] of_string_opt : string -> option(int)
    ##args(str)
{
    try {
        js_some(%%BslNumber.Int.of_string%%(str))
    } catch(e) {
        return js_none;
    }
}

##register [pure] of_float : float -> int
  ##args(a)
  {
    if (a<0)
      return Math.ceil(a); // because Math.floor(-3.1) = 4 and not 3
    else
      return Math.floor(a);
  }

// For bitwise you get: floats -> 32-bit ints -> op -> 32-bit ints -> float
// If you try bitwise ops outside of the 32-bit range the results just don't make sense, or are imprecise
// I think it would be safer to just return NaN for values outside this range (or undefined?)

##register [pure] op_land : int, int -> int
##args(n, m)
{
  if (n < IMIN32 || n > IMAX32 || m < IMIN32 || m > IMAX32) return NaN;
  return n & m;
}

##register [pure] op_lor : int, int -> int
##args(n, m)
{
  if (n < IMIN32 || n > IMAX32 || m < IMIN32 || m > IMAX32) return NaN;
  return n | m;
}

##register [pure] op_lxor : int, int -> int
##args(n, m)
{
  if (n < IMIN32 || n > IMAX32 || m < IMIN32 || m > IMAX32) return NaN;
  return n ^ m;
}

##register [pure] op_lnot : int -> int
##args(n)
{
  if (n < IMIN32 || n > IMAX32) return NaN;
  return ~n;
}

##register [pure] op_lsl : int, int -> int
##args(n, m)
//function op_lsl(n,m)
{
  if (m >= 32 || n < IMIN32 || n > IMAX32) return NaN;
  return n << m;
}

##register [pure] op_lsr : int, int -> int
##args(n, m)
//function op_lsr(n,m)
{
  if (m >= 32) return 0;
  if (n < IMIN32 || n > IMAX32) return NaN;
  return n >>> m;
}

##register [pure] op_asr : int, int -> int
##args(n, m)
//function op_asr(n, m)
{
  if (n < IMIN32 || n > IMAX32) return NaN;
  if (m >= 32) return (n & 0x80000000) ? -1 : 0;
  return n >> m;
}

##register [pure] leq:int, int -> bool
##args(c1,c2)
{
   return c1 <= c2
}

##register [pure] geq:int, int -> bool
##args(c1,c2)
{
   return c1 >= c2
}

##register [pure] ordering: int,int -> opa[Order.ordering]
##args(c1,c2)
{
    if(c1<c2) return result_lt
    if(c1==c2) return result_eq
    return result_gt
}

##endmodule

##module BslInt64

// Note these are *unsigned* int64 routines.

/* Explanation:  Why do we have all these strange routines here?
 * Basically because JS ints are 53 bits in accuracy but that
 * bitwise operations are restricted to 32-bit *sign-extended*
 * ints.  That is, ~0 === -1.  Since we implement int64 as:
 * {h:<high 32 bits>, l:<low 32 bits>} we can't tolerate any of
 * the sign extension which goes on, we need {h:0x80000000, ...}
 * and not {h:-0x80000000, ...}.  To prevent JS from sign extending
 * we have to do our bitwise ops as:
 * if (op x) has bit 31 set then ((op x) resulting in bit 31 not set)+0x80000000.
 * This is greatly inconvenient and slow but seems to work.
 */

/* Debug code
function to_hex_(i) {
  if (typeof i == 'undefined') return "undefind";
  var s = i.toString(16);
  while (s.length < 8) s = "0"+s;
  return s;
}
function p(i) { return "{h:"+to_hex_(i.h)+", l:"+to_hex_(i.l)+"}"; }
function q(qr) { return "{q:"+p(qr.q)+", r:"+p(qr.r)+"}"; }
*/

// These get passed around an awful lot...
// ... so we'll prevent them from being accidentally modified.
function NAN() { return {h:NaN, l:NaN}; }
function ZERO() { return {h:0, l:0}; }
function ONE() { return {h:0, l:1}; }
function INFINITY() { return {h:Infinity, l:Infinity}; }
function MAX_INT() { return {h:0xffffffff, l:0xffffffff}; }

function is_nan(i) { return isNaN(i.h) || isNaN(i.l); }
function is_zero(i) { return i.h === 0 && i.l === 0; }
function is_one(i) { return i.h === 0 && i.l === 1; }
function is_finite(i) { return isFinite(i.h) && isFinite(i.l); }

// For debugging...
##register catch : ( -> 'a) -> opa[outcome('a,string)]
##args(f)
{
  try {
    return {success:f()};
  } catch (err) {
    return {failure:err};
  }
}

##register max_int : -> int64
##args()
{
  return MAX_INT();
}

##register is_NaN : int64 -> bool
##args(i)
{
  return is_nan(i);
}

##register of_int : int -> int64
##args(i)
//function of_int(i)
{
  if (i >= 0 && i <= IMAX32) { return {h:0, l:i}; };
  if (i < 0 || i < IMIN53 || i > IMAX53) { return NAN(); };
  var h = Math.floor(i / POW2_32);
  var l = i % POW2_32;
  return {h:h, l:l};
}

##register to_int : int64 -> int
##args(i64)
//function to_int(i64)
{
  if (is_nan(i64)) return NAN();
  if (i64.h > 0x1fffff) throw "Int64.to_int: int64 too big for int";
  return (i64.h * 0x100000000) + i64.l;
}

##register succ : int64 -> int64
##args(i)
//function succ(i)
{
  if (i.l === 0xffffffff)
    if (i.h === 0xffffffff)
      throw "Int64.succ: overflow";
    else
      return {h:i.h+1, l:0};
  else
    return {h:i.h, l:i.l+1};
}

##register pred : int64 -> int64
##args(i)
//function pred(i)
{
  if (i.l === 0)
    if (i.h === 0)
      throw "Int64.pred: underflow";
    else
      return {h:i.h-1, l:0xffffffff};
  else
    return {h:i.h, l:i.l-1};
}

##register add : int64, int64 -> int64
##args(i1,i2)
//function add(i1, i2)
{
  return adde(i1, i2, "Int64.add: overflow");
}

function adde(i1, i2, err)
{
  if (is_nan(i1) || is_nan(i2)) return NAN();
  if (is_zero(i1)) return i2;
  if (is_zero(i2)) return i1;
  var ll = i1.l + i2.l;
  var c = 0;
  if (ll > 0xffffffff) { c = 1; ll -= 0x100000000; };
  var hh = i1.h + i2.h + c;
  if (hh > 0xffffffff) throw err;
  return {h:hh, l:ll};
}

##register sub : int64, int64 -> int64
##args(i1,i2)
//function sub(i1, i2)
{
  if (is_nan(i1) || is_nan(i2)) return NAN();
  if (is_zero(i2)) return i1;
  var ll = i1.l - i2.l;
  var b = 0;
  if (ll < 0) { b = 1; ll += 0x100000000; };
  var hh = i1.h - i2.h - b;
  if (hh < 0) throw "Int64.sub: underflow";
  return {h:hh, l:ll};
}

function mul16n(i32hh, i32hl, i32lh, i32ll, i16, n, err) {
  var tmp = i32ll * i16;
  var ll = tmp & 0xffff;
  tmp = i32lh * i16 + (tmp >>> 16);
  var lh = tmp & 0xffff;
  tmp = i32hl * i16 + (tmp >>> 16);
  var hl = tmp & 0xffff;
  var hh = i32hh * i16 + (tmp >>> 16);
  switch (n) {
  case 0:
    if (hh > 0xffff) throw err;
    return {h:hh*0x10000+hl, l:lh*0x10000+ll};
  case 16:
    if (hh > 0 || hl > 0xffff) throw err;
    return {h:hl*0x10000+lh, l:ll*0x10000};
  case 32:
    if (hh > 0 || hl > 0 || lh > 0xffff) throw err;
    return {h:lh*0x10000+ll, l:0};
  case 48:
    if (hh > 0 || hl > 0 || lh > 0 || ll > 0xffff) throw err;
    return {h:ll*0x10000, l:0};
  default:
    throw "Int64.mul: bad shift";
  }
}

function mule(i1, i2, err) {
  if (is_nan(i1) || is_nan(i2)) return NAN();
  if (is_zero(i1) || is_zero(i2)) return ZERO();
  if (is_one(i1)) return i2;
  if (is_one(i2)) return i1;
  var i1hh = i1.h >>> 16, i1hl = i1.h & 0xffff, i1lh = i1.l >>> 16, i1ll = i1.l & 0xffff;
  var i2hh = i2.h >>> 16, i2hl = i2.h & 0xffff, i2lh = i2.l >>> 16, i2ll = i2.l & 0xffff;
  var a = mul16n(i1hh, i1hl, i1lh, i1ll, i2ll,  0, err);
  var b = mul16n(i1hh, i1hl, i1lh, i1ll, i2lh, 16, err);
  var c = mul16n(i1hh, i1hl, i1lh, i1ll, i2hl, 32, err);
  var d = mul16n(i1hh, i1hl, i1lh, i1ll, i2hh, 48, err);
  function add(x,y) { return adde(x,y,err); }
  return add(add(a,b), add(c,d));
}

##register mul : int64, int64 -> int64
##args(i1,i2)
//function mul(i1,i2)
{
  return mule(i1,i2,"Int64.mul: overflow");
}

var btab = [0x00000001, 0x00000002, 0x00000004, 0x00000008,
            0x00000010, 0x00000020, 0x00000040, 0x00000080,
            0x00000100, 0x00000200, 0x00000400, 0x00000800,
            0x00001000, 0x00002000, 0x00004000, 0x00008000,
            0x00010000, 0x00020000, 0x00040000, 0x00080000,
            0x00100000, 0x00200000, 0x00400000, 0x00800000,
            0x01000000, 0x02000000, 0x04000000, 0x08000000,
            0x10000000, 0x20000000, 0x40000000, 0x80000000];

function setb(x, msk) {
  if (msk === 0x80000000) {
    if (x & 0x80000000) return x;
    return x + 0x80000000; // <-- this seems to be the only way of preventing JS from sign-extending bit 31
  };
  if (x & 0x80000000) {
    return ((x & 0x7fffffff) | msk) + 0x80000000; // <-- !!!!! you've got to be kidding
  };
  return x | msk;
}

function shftleft(x) {
  if (x & 0x40000000) return ((x & 0xbfffffff) << 1) + 0x80000000; // <-- and again
  return x << 1;
}

function setbit(v, bn) {
  if (bn > 63) return v;
  if (bn > 31)
    return {h:setb(v.h,btab[bn-32]), l:v.l};
  else
    return {h:v.h, l:setb(v.l,btab[bn])};
}

function shft128(x) {
  var y = [0,0,0,0];
  y[0] = shftleft(x[0]);
  if (x[1] & 0x80000000) y[0] = setb(y[0],1);
  y[1] = shftleft(x[1]);
  if (x[2] & 0x80000000) y[1] = setb(y[1],1);
  y[2] = shftleft(x[2]);
  if (x[3] & 0x80000000) y[2] = setb(y[2],1);
  y[3] = shftleft(x[3]);
  return y;
}

function sub128(i1, i2)
{
  var l3 = i1[3] - i2[3];
  var b = 0;
  if (l3 < 0) { b = 1; l3 += 0x100000000; };
  var l2 = i1[2] - i2[2] - b;
  b = 0;
  if (l2 < 0) { b = 1; l2 += 0x100000000; };
  var l1 = i1[1] - i2[1] - b;
  b = 0;
  if (l1 < 0) { b = 1; l1 += 0x100000000; };
  var l0 = i1[0] - i2[0] - b;
  if (l0 < 0) throw "Int64.sub128: underflow";
  return [l0,l1,l2,l3];
}

// Naive, slow but accurate.
// Try using 53-bit division and get it to divide 64-bits without sign-extending or truncating the results.
function qr64(N, D) {
  if (is_nan(N) || is_nan(D)) return {q:NAN(), r:NAN()};
  if (is_zero(D)) return {q:INFINITY(), r:NAN()};
  if (is_one(D)) return {q:N, r:ZERO()};
  if (BslNumber_BslInt64_op_gt(D,N)) return {q:ZERO(), r:N};
  var P = [0,0,N.h,N.l];
  var D = [D.h,D.l,0,0];
  var Q = ZERO();
  for (var i = 63; i >= 0; i--) {
    P = shft128(P);
    if ((P[0] === D[0]) ? ((P[1] === D[1]) ? ((P[2] === D[2]) ? P[3] >= D[3] : P[2] >= D[2]) : P[1] >= D[1]) : P[0] >= D[0]) {
      Q = setbit(Q, i);
      P = sub128(P, D);
    };
  }
  return {q:Q, r:{h:P[0], l:P[1]}};
}

##register div : int64, int64 -> int64
##args(N, D)
//function div(N, D)
{
  return qr64(N, D).q;
}

##register rem : int64, int64 -> int64
##args(N, D)
//function rem(N, D)
{
  return qr64(N, D).r;
}

##register op_eq : int64, int64 -> bool
##args(i1,i2)
//function op_eq(i1, i2)
{
  return (i1.h === i2.h) && (i1.l === i2.l);
}

##register op_ne : int64, int64 -> bool
##args(i1,i2)
//function op_ne(i1, i2)
{
  return (i1.h !== i2.h) || (i1.l !== i2.l);
}

##register op_gt : int64, int64 -> bool
##args(i1,i2)
//function op_gt(i1, i2)
{
  return (i1.h === i2.h) ? i1.l > i2.l : i1.h > i2.h;
}

##register op_ge : int64, int64 -> bool
##args(i1,i2)
//function op_ge(i1, i2)
{
  return (i1.h === i2.h) ? i1.l >= i2.l : i1.h >= i2.h;
}

##register op_lt : int64, int64 -> bool
##args(i1,i2)
//function op_lt(i1, i2)
{
  return (i1.h === i2.h) ? i1.l < i2.l : i1.h < i2.h;
}

##register op_le : int64, int64 -> bool
##args(i1,i2)
//function op_le(i1, i2)
{
  return (i1.h === i2.h) ? i1.l <= i2.l : i1.h <= i2.h;
}

##register to_string_radix : int64, int -> string
##args(i, radix)
//function to_string_radix(i, radix)
{
  if (radix < 2 || radix > 16) throw ("Int64.to_string: bad radix "+radix);
  if (is_nan(i)) return "NaN";
  if (is_zero(i)) return "0";
  if (is_one(i)) return "1";
  if (!is_finite(i)) return "Infinity";
  var strs = "0123456789abcdef";
  var s = [], R={h:0, l:radix};
  while (!is_zero(i)) {
    qr = qr64(i, R);
    if (qr.r.l >= radix) throw "Int64.to_string: bad number";
    s.push(strs[qr.r.l]);
    i = qr.q;
  }
  return s.reverse().join("");
}

##register to_string : int64 -> string
##args(i)
//function to_string(i)
{
  return BslNumber_BslInt64_to_string_radix(i, 10);
}

##register of_string_radix : string, int -> int64
##args(s, radix)
//function of_string_radix(s, radix)
{
  var tab = { '0': 0, '1': 1, '2': 2, '3': 3, '4': 4, '5': 5, '6': 6, '7': 7, '8': 8, '9': 9,
              'a': 10, 'b': 11, 'c': 12, 'd': 13, 'e': 14, 'f': 15,
              'A': 10, 'B': 11, 'C': 12, 'D': 13, 'E': 14, 'F': 15 };
  if (radix < 2 || radix > 16) throw ("Int64.of_string: bad radix "+radix);
  var x = ZERO();
  var err = "Int64.of_string: number too large for int64";
  for (var i = 0; i < s.length; i++) {
    var dig = tab[s[i]];
    if (typeof dig == 'undefined' || dig >= radix)
      throw ("Int64.of_string: bad digit "+dig);
    x = adde(mule(x, {h:0, l:radix}, err), {h:0, l:dig}, err);
  }
  return x;
}

##register of_string : string -> int64
##args(s)
//function of_string(s)
{
  return BslNumber_BslInt64_of_string_radix(s, 10);
}

function land(i1,i2) {
  if ((i1 & 0x80000000) && (i2 & 0x80000000)) {
    return ((i1 & 0x7fffffff) & (i2 & 0x7fffffff)) + 0x80000000;
  }
  return i1 & i2;
}

##register logand : int64, int64 -> int64
##args(i1,i2)
//function logand(i1,i2)
{
  return {h:land(i1.h,i2.h), l:land(i1.l,i2.l)};
}

function lor(i1,i2) {
  if ((i1 & 0x80000000) || (i2 & 0x80000000)) {
    return ((i1 & 0x7fffffff) | (i2 & 0x7fffffff)) + 0x80000000;
  }
  return i1 | i2;
}

##register logor : int64, int64 -> int64
##args(i1,i2)
//function logor(i1,i2)
{
  return {h:lor(i1.h,i2.h), l:lor(i1.l,i2.l)};
}

function lxor(i1,i2) {
  if (((i1 & 0x80000000) && !(i2 & 0x80000000)) || (!(i1 & 0x80000000) && (i2 & 0x80000000))) {
    return ((i1 & 0x7fffffff) ^ (i2 & 0x7fffffff)) + 0x80000000;
  }
  return i1 ^ i2;
}

##register logxor : int64, int64 -> int64
##args(i1,i2)
//function logxor(i1,i2)
{
  return {h:lxor(i1.h,i2.h), l:lxor(i1.l,i2.l)};
}

function lnot(i) {
  if (!(i & 0x80000000)) {
    return (~(i | 0x80000000)) + 0x80000000;
  }
  return ~i;
}

##register lognot : int64 -> int64
##args(i)
//function lognot(i)
{
  return {h:lnot(i.h), l:lnot(i.l)};
}

function lsl(i,n) {
  if (n <= 0) return {h:0, l:i};
  if (n > 63) return ZERO();
  if (n === 32) return {h:i, l:0};
  if (n > 32) {
    n = n - 32;
    if (i & btab[31-n]) {
      return {h:((i & lnot(btab[31-n])) << n) + 0x80000000, l:0};
    }
    return {h:i<<n, l:0};
  }
  if (i & btab[31-n]) {
    return {h:i>>>(32-n), l:((i & lnot(btab[31-n])) << n) + 0x80000000};
  }
  return {h:i>>>(32-n), l:i<<n};
}

##register shift_left : int64, int -> int64
##args(i,n)
//function shift_left(i,n)
{
  if (n <= 0) return i;
  if (n > 63) return ZERO();
  if (n === 32) return {h:i.l, l:0};
  var s1 = lsl(i.h,n);
  var s2 = lsl(i.l,n);
  return {h:lor(s1.l,s2.h), l:s2.l};
}

function asr_(i, n) {
  if (n === 0) return i;
  if (n >= 32) return (i & 0x80000000) ? 0xffffffff : 0;
  var msks = [0x80000000, 0xc0000000, 0xe0000000, 0xf0000000,
              0xf8000000, 0xfc000000, 0xfe000000, 0xff000000,
              0xff800000, 0xffc00000, 0xffe00000, 0xfff00000,
              0xfff80000, 0xfffc0000, 0xfffe0000, 0xffff0000,
              0xffff8000, 0xffffc000, 0xffffe000, 0xfffff000,
              0xfffff800, 0xfffffc00, 0xfffffe00, 0xffffff00,
              0xffffff80, 0xffffffc0, 0xffffffe0, 0xfffffff0,
              0xfffffff8, 0xfffffffc, 0xfffffffe, 0xffffffff];
  if (i & 0x80000000)
    return (i >>> n) + msks[n-1];
  else
    return i >>> n;
}

function asr(i,n) {
  if (!(i & 0x80000000)) return lsr(i, n);
  if (n <= 0) return {h:i, l:0};
  if (n > 63) return (i & 0x80000000) ? MAX_INT() : ZERO();
  if (n === 32) return {h:(i & 0x80000000) ? 0xffffffff : 0, l:i};
  if (n > 32) return {h:(i & 0x80000000) ? 0xffffffff : 0, l:asr_(i,n-32)};
  if (i & btab[n-1]) {
    return {h:asr_(i,n), l:((i & lnot(btab[n-1])) << (32-n)) + 0x80000000};
  }
  return {h:asr_(i,n), l:i<<(32-n)};
}

##register shift_right : int64, int -> int64
##args(i,n)
//function shift_right(i,n)
{
  if (!(i.h & 0x80000000)) return shift_right_logical_(i,n);
  if (n <= 0) return i;
  if (n > 63) return MAX_INT();
  if (n === 32) return {h:0xffffffff, l:i.h};
  var s1 = asr(i.h,n);
  var s2 = asr(i.l,n);
  return {h:s1.h, l:lor(s1.l,s2.h)};
}

function lsr(i,n) {
  if (n <= 0) return {h:i, l:0};
  if (n > 63) return ZERO();
  if (n === 32) return {h:0, l:i};
  if (n > 32) return {h:0, l:i>>>(n-32)};
  if (i & btab[n-1]) {
    return {h:i>>>n, l:((i & lnot(btab[n-1])) << (32-n)) + 0x80000000};
  }
  return {h:i>>>n, l:i<<(32-n)};
}

##register shift_right_logical : int64, int -> int64
##args(i,n)
//function shift_right_logical(i,n)
{
  return shift_right_logical_(i,n);
}

function shift_right_logical_(i,n)
{
  if (n <= 0) return i;
  if (n > 63) return ZERO();
  if (n === 32) return {h:0, l:i.h};
  var s1 = lsr(i.h,n);
  var s2 = lsr(i.l,n);
  return {h:s1.h, l:lor(s1.l,s2.h)};
}

##endmodule

##module Float \ bsl_float

##register [pure] of_int : int -> float
  ##args(a)
  {
    return a;
  }

##register [pure] of_string : string -> float
  ##args(v)
  {
    return parseFloat(v)
  }

##register [pure] of_string_opt : string -> option(float)
    ##args(str)
{
    try {
        js_some(%%BslNumber.Float.of_string%%(str))
    } catch(e) {
        return js_none;
    }
}

  // transforms the string so that it is compatible with the mlbsl
  // (see the comment there)
##register [pure] to_string : float -> string
  ##args(v)
{
    var str = ""+v;
    if (str.indexOf('.') >= 0 || str.indexOf('e') >= 0 || str[0] == 'N' || str[0] == 'I' || str[1] == 'I') {
        return str; //Printing corresponds to server-side printing
    } else {
        return str + ".0";//Printing needs to be adjusted
    }
}

  // should also be compatible with mlbsl
##register [pure] to_formatted_string : bool, option(int), float -> string
  ##args(always_dot,decimals_option,f)
  {
      var str = ""+f;
      if ('none' in decimals_option) {
          if (!always_dot || (str.indexOf('.') >= 0) || str.indexOf('e') >= 0 || str[0] == 'N' || str[0] == 'I' || str[1] == 'I') {
              // either js stringification already doesn't print the dot when not necessary
              // or if there is already one, nothing to do
              // or we have a '1e-88' kind of float and we don't add any point
              // or we have NaN or Infinity or -Infinity, and we can't add a decimal point
              return str;
          } else {
              // we want a dot, and didn't find one in str, so we add it ourselves
              return str + ".0";
          }
      } else {
          if (always_dot || str.indexOf('.') >= 0) {
              // either, we want a dot, we will have it when calling toFixed
              // or we have a real float (there is a dot), keep the dot, but truncate the string
              return f.toFixed(decimals_option.some);
          } else {
              // int or special cases, or scientific notation
              return str;
          }
      }
  }

##register [pure] round    \ `Math.round`   : float -> int
##register [pure] ceil     \ `Math.ceil`    : float -> float
##register [pure] floor    \ `Math.floor`   : float -> float

##register [pure] leq:float, float -> bool
##args(c1,c2)
{
   return c1 <= c2
}

##register [pure] lt:float, float -> bool
##args(c1,c2)
{
   return c1 < c2
}

##register [pure] eq:float, float -> bool
##args(c1,c2)
{
   return c1 == c2
}

##register [pure] geq:float, float -> bool
##args(c1,c2)
{
   return c1 >= c2
}

##register [pure] gt:float, float -> bool
##args(c1,c2)
{
   return c1 > c2
}

##register [pure] neq:float, float -> bool
##args(c1,c2)
{
   return c1 != c2
}

##register [pure] comparison: float,float -> opa[Order.comparison]
##args(c1,c2)
{
    if(isNaN(c1) || isNaN(c2)) return result_neq
    if(c1<c2) return result_lt
    if(c1==c2) return result_eq
    return result_gt
}

function code(i) {
  // Ridiculous, there has to be a better way than this to prevent Javascript from casting ints to strings.
  var tab =
    ["\x00","\x01","\x02","\x03","\x04","\x05","\x06","\x07","\x08","\x09","\x0a","\x0b","\x0c","\x0d","\x0e","\x0f",
     "\x10","\x11","\x12","\x13","\x14","\x15","\x16","\x17","\x18","\x19","\x1a","\x1b","\x1c","\x1d","\x1e","\x1f",
     "\x20","\x21","\x22","\x23","\x24","\x25","\x26","\x27","\x28","\x29","\x2a","\x2b","\x2c","\x2d","\x2e","\x2f",
     "\x30","\x31","\x32","\x33","\x34","\x35","\x36","\x37","\x38","\x39","\x3a","\x3b","\x3c","\x3d","\x3e","\x3f",
     "\x40","\x41","\x42","\x43","\x44","\x45","\x46","\x47","\x48","\x49","\x4a","\x4b","\x4c","\x4d","\x4e","\x4f",
     "\x50","\x51","\x52","\x53","\x54","\x55","\x56","\x57","\x58","\x59","\x5a","\x5b","\x5c","\x5d","\x5e","\x5f",
     "\x60","\x61","\x62","\x63","\x64","\x65","\x66","\x67","\x68","\x69","\x6a","\x6b","\x6c","\x6d","\x6e","\x6f",
     "\x70","\x71","\x72","\x73","\x74","\x75","\x76","\x77","\x78","\x79","\x7a","\x7b","\x7c","\x7d","\x7e","\x7f",
     "\x80","\x81","\x82","\x83","\x84","\x85","\x86","\x87","\x88","\x89","\x8a","\x8b","\x8c","\x8d","\x8e","\x8f",
     "\x90","\x91","\x92","\x93","\x94","\x95","\x96","\x97","\x98","\x99","\x9a","\x9b","\x9c","\x9d","\x9e","\x9f",
     "\xa0","\xa1","\xa2","\xa3","\xa4","\xa5","\xa6","\xa7","\xa8","\xa9","\xaa","\xab","\xac","\xad","\xae","\xaf",
     "\xb0","\xb1","\xb2","\xb3","\xb4","\xb5","\xb6","\xb7","\xb8","\xb9","\xba","\xbb","\xbc","\xbd","\xbe","\xbf",
     "\xc0","\xc1","\xc2","\xc3","\xc4","\xc5","\xc6","\xc7","\xc8","\xc9","\xca","\xcb","\xcc","\xcd","\xce","\xcf",
     "\xd0","\xd1","\xd2","\xd3","\xd4","\xd5","\xd6","\xd7","\xd8","\xd9","\xda","\xdb","\xdc","\xdd","\xde","\xdf",
     "\xe0","\xe1","\xe2","\xe3","\xe4","\xe5","\xe6","\xe7","\xe8","\xe9","\xea","\xeb","\xec","\xed","\xee","\xef",
     "\xf0","\xf1","\xf2","\xf3","\xf4","\xf5","\xf6","\xf7","\xf8","\xf9","\xfa","\xfb","\xfc","\xfd","\xfe","\xff"
     ];
  return tab[i];
}

function uncode(s) {
  // Even more ridiculous
  var tab = {
    '\x00':0x00, '\x01':0x01, '\x02':0x02, '\x03':0x03, '\x04':0x04, '\x05':0x05, '\x06':0x06, '\x07':0x07,
    '\x08':0x08, '\x09':0x09, '\x0a':0x0a, '\x0b':0x0b, '\x0c':0x0c, '\x0d':0x0d, '\x0e':0x0e, '\x0f':0x0f,
    '\x10':0x10, '\x11':0x11, '\x12':0x12, '\x13':0x13, '\x14':0x14, '\x15':0x15, '\x16':0x16, '\x17':0x17,
    '\x18':0x18, '\x19':0x19, '\x1a':0x1a, '\x1b':0x1b, '\x1c':0x1c, '\x1d':0x1d, '\x1e':0x1e, '\x1f':0x1f,
    '\x20':0x20, '\x21':0x21, '\x22':0x22, '\x23':0x23, '\x24':0x24, '\x25':0x25, '\x26':0x26, '\x27':0x27,
    '\x28':0x28, '\x29':0x29, '\x2a':0x2a, '\x2b':0x2b, '\x2c':0x2c, '\x2d':0x2d, '\x2e':0x2e, '\x2f':0x2f,
    '\x30':0x30, '\x31':0x31, '\x32':0x32, '\x33':0x33, '\x34':0x34, '\x35':0x35, '\x36':0x36, '\x37':0x37,
    '\x38':0x38, '\x39':0x39, '\x3a':0x3a, '\x3b':0x3b, '\x3c':0x3c, '\x3d':0x3d, '\x3e':0x3e, '\x3f':0x3f,
    '\x40':0x40, '\x41':0x41, '\x42':0x42, '\x43':0x43, '\x44':0x44, '\x45':0x45, '\x46':0x46, '\x47':0x47,
    '\x48':0x48, '\x49':0x49, '\x4a':0x4a, '\x4b':0x4b, '\x4c':0x4c, '\x4d':0x4d, '\x4e':0x4e, '\x4f':0x4f,
    '\x50':0x50, '\x51':0x51, '\x52':0x52, '\x53':0x53, '\x54':0x54, '\x55':0x55, '\x56':0x56, '\x57':0x57,
    '\x58':0x58, '\x59':0x59, '\x5a':0x5a, '\x5b':0x5b, '\x5c':0x5c, '\x5d':0x5d, '\x5e':0x5e, '\x5f':0x5f,
    '\x60':0x60, '\x61':0x61, '\x62':0x62, '\x63':0x63, '\x64':0x64, '\x65':0x65, '\x66':0x66, '\x67':0x67,
    '\x68':0x68, '\x69':0x69, '\x6a':0x6a, '\x6b':0x6b, '\x6c':0x6c, '\x6d':0x6d, '\x6e':0x6e, '\x6f':0x6f,
    '\x70':0x70, '\x71':0x71, '\x72':0x72, '\x73':0x73, '\x74':0x74, '\x75':0x75, '\x76':0x76, '\x77':0x77,
    '\x78':0x78, '\x79':0x79, '\x7a':0x7a, '\x7b':0x7b, '\x7c':0x7c, '\x7d':0x7d, '\x7e':0x7e, '\x7f':0x7f,
    '\x80':0x80, '\x81':0x81, '\x82':0x82, '\x83':0x83, '\x84':0x84, '\x85':0x85, '\x86':0x86, '\x87':0x87,
    '\x88':0x88, '\x89':0x89, '\x8a':0x8a, '\x8b':0x8b, '\x8c':0x8c, '\x8d':0x8d, '\x8e':0x8e, '\x8f':0x8f,
    '\x90':0x90, '\x91':0x91, '\x92':0x92, '\x93':0x93, '\x94':0x94, '\x95':0x95, '\x96':0x96, '\x97':0x97,
    '\x98':0x98, '\x99':0x99, '\x9a':0x9a, '\x9b':0x9b, '\x9c':0x9c, '\x9d':0x9d, '\x9e':0x9e, '\x9f':0x9f,
    '\xa0':0xa0, '\xa1':0xa1, '\xa2':0xa2, '\xa3':0xa3, '\xa4':0xa4, '\xa5':0xa5, '\xa6':0xa6, '\xa7':0xa7,
    '\xa8':0xa8, '\xa9':0xa9, '\xaa':0xaa, '\xab':0xab, '\xac':0xac, '\xad':0xad, '\xae':0xae, '\xaf':0xaf,
    '\xb0':0xb0, '\xb1':0xb1, '\xb2':0xb2, '\xb3':0xb3, '\xb4':0xb4, '\xb5':0xb5, '\xb6':0xb6, '\xb7':0xb7,
    '\xb8':0xb8, '\xb9':0xb9, '\xba':0xba, '\xbb':0xbb, '\xbc':0xbc, '\xbd':0xbd, '\xbe':0xbe, '\xbf':0xbf,
    '\xc0':0xc0, '\xc1':0xc1, '\xc2':0xc2, '\xc3':0xc3, '\xc4':0xc4, '\xc5':0xc5, '\xc6':0xc6, '\xc7':0xc7,
    '\xc8':0xc8, '\xc9':0xc9, '\xca':0xca, '\xcb':0xcb, '\xcc':0xcc, '\xcd':0xcd, '\xce':0xce, '\xcf':0xcf,
    '\xd0':0xd0, '\xd1':0xd1, '\xd2':0xd2, '\xd3':0xd3, '\xd4':0xd4, '\xd5':0xd5, '\xd6':0xd6, '\xd7':0xd7,
    '\xd8':0xd8, '\xd9':0xd9, '\xda':0xda, '\xdb':0xdb, '\xdc':0xdc, '\xdd':0xdd, '\xde':0xde, '\xdf':0xdf,
    '\xe0':0xe0, '\xe1':0xe1, '\xe2':0xe2, '\xe3':0xe3, '\xe4':0xe4, '\xe5':0xe5, '\xe6':0xe6, '\xe7':0xe7,
    '\xe8':0xe8, '\xe9':0xe9, '\xea':0xea, '\xeb':0xeb, '\xec':0xec, '\xed':0xed, '\xee':0xee, '\xef':0xef,
    '\xf0':0xf0, '\xf1':0xf1, '\xf2':0xf2, '\xf3':0xf3, '\xf4':0xf4, '\xf5':0xf5, '\xf6':0xf6, '\xf7':0xf7,
    '\xf8':0xf8, '\xf9':0xf9, '\xfa':0xfa, '\xfb':0xfb, '\xfc':0xfc, '\xfd':0xfd, '\xfe':0xfe, '\xff':0xff
  };
  return tab[s];
}

function a2s(a) {
  var s = "";
  for (var i = 0; i < a.length; i++) { s += code(a[i]) };
  return s;
}

function s2a(s,start,length) {
  start = (typeof start == 'undefined') ? 0 : start;
  var end =
    (typeof length == 'undefined') ? s.length :
    (start + length > s.length) ? s.length : start + length;
  var a = new Array(end - start - 1);
  for (var i = start, j = 0; i < end; i++, j++) { a[j] = uncode(s[i]) };
  return a;
}

function clen(c) {
  if (c >= 0 && c <= 0xff) return 1;
  if (c >= 0 && c <= 0xffff) return 2;
  if (c >= 0 && c <= 0xffffffff) return 4;
  return 8;
}

function slen(s,start,length) {
  var size = 0, i;
  start = (typeof start == 'undefined') ? 0 : start;
  var end =
    (typeof length == 'undefined') ? s.length :
    (start + length > s.length) ? s.length : start + length;
  for (i = start; i < end; size += clen(s.charCodeAt(i++)));
  return size;
}

// This routine flattens out unicode characters, "\uabcd" -> <Buffer ab cd>
function s2bj(s,start,length,b,j) {
  start = (typeof start == 'undefined') ? 0 : start;
  var end =
    (typeof length == 'undefined') ? s.length :
    (start + length > s.length) ? s.length : start + length;
  var i;
  for (i = start; i < end; i++) {
    var c = s.charCodeAt(i);
    if (c >= 0 && c <= 0xff) {
      b[j++] = c;
    } else if (c >= 0 && c <= 0xffff) {
      b[j++] = (c >> 8) & 0xff;
      b[j++] =  c       & 0xff;
    } else if (c >= 0 && c <= 0xffffffff) {
      b[j++] = (c >> 24) & 0xff;
      b[j++] = (c >> 16) & 0xff;
      b[j++] = (c >>  8) & 0xff;
      b[j++] =  c        & 0xff;
    } else {
      throw "BslNumber.s2b: bad char code";
    };
  };
  return b;
}

function s2b(s,start,length) {
  var b = new Buffer(slen(s,start,length)), j = 0;
  return s2bj(s,start,length,b,j);
}

function dump(s)
{
  var b = s2b(s)
  var i = 0, d = "";
  while (i < b.length) {
    var h = "", a = "", pos = i.toString(16);
    while (pos.length < 4) { pos = "0" + pos; };
    for (var j = 0; i < b.length && j < 16; i++,j++) {
      var ch = b[i];
      var ac = (ch >= 0x20 && ch < 0x7f) ? code(b[i]) : ".";
      var hx = ch.toString(16);
      if (hx.length == 1) hx = "0" + hx;
      var sp = (i == b.length - 1) ? "" : " ";
      h += hx + sp;
      a += ac;
    };
    while (h.length < 3*16) { h += " "; };
    d += pos + " " + h + " " + a + "\n";
  };
  return d;
}

/* Same but for 64-bit floating point numbers. */

##register embed_float_le : float -> string
##args(f)
//function embed_float_le(f)
{
  var b = new Buffer(8);
  b.writeDoubleLE(f, 0);
  return a2s(b);
}

##register embed_float_be : float -> string
##args(f)
//function embed_float_be(f)
{
  var b = new Buffer(8);
  b.writeDoubleBE(f, 0);
  return a2s(b);
}

##register unembed_float_le: string, int -> float
##args(s, offset)
{
  return (s2b(s,offset,8)).readDoubleLE(0);
}

##register unembed_float_be: string, int -> float
##args(s, offset)
{
  return (s2b(s,offset,8)).readDoubleBE(0);
}

##endmodule

##module Math \ bsl_math

##register [pure] sqrt_i : int -> int
##args(n)
{
    return Math.floor(Math.sqrt(n));
}

##register [pure] log     \ `Math.log`     : float -> float
##register [pure] sqrt_f  \ `Math.sqrt`    : float -> float
##register [pure] exp     \ `Math.exp`     : float -> float

##register [pure] abs_i   \ `Math.abs`     : int -> int
##register [pure] abs_f   \ `Math.abs`     : float -> float

##register [pure] ceil    \ `Math.ceil`    : float -> float
##register [pure] floor   \ `Math.floor`   : float -> float

##register [pure] sin     \ `Math.sin`     : float -> float
##register [pure] cos     \ `Math.cos`     : float -> float
##register [pure] tan     \ `Math.tan`     : float -> float

##register [pure] asin    \ `Math.asin`    : float -> float
##register [pure] acos    \ `Math.acos`    : float -> float
##register [pure] atan    \ `Math.atan`    : float -> float

##register [pure] isNaN   \ `isNaN`        : float -> bool

##register [pure] is_infinite : float -> bool
##args(n)
{
    return !(isFinite(n) || isNaN(n));
}

##register [pure] is_normal \ `isFinite` : float -> bool

##endmodule

##module Random
##register int : int -> int
  ##args(n)
  {
    return Math.floor(Math.random() * n)
  }
##register float : float -> float
  ##args(n)
  {
    return Math.random() * n
  }

##register random_init : -> void
  ##args()
  {
      return ;
  }

function makeStringFromChars(chars, len) {
    var s = "";
    for (var i = 0; i < len; ++i)
	s += chars.charAt(Math.floor(Math.random() * chars.length));
    return s;
}

##register generic_string : string, int -> string
    ##args(chars, len)
{
    return (makeStringFromChars(chars, len));
}

##register string : int -> string
    ##args(len)
{
    var chars = "abcdefghijklmnopqrstuvwxyz";
    return makeStringFromChars(chars, len);
}

##register base64 : int -> string
    ##args(len)
{
    var chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
    return makeStringFromChars(chars, len)
  }

##register base64_url : int -> string
    ##args(len)
{
    var chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_";
    return makeStringFromChars(chars, len)
  }

##endmodule