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# Cf. http://llvm.org/docs/tutorial/LangImpl6.html#kicking-the-tires
#
extern printd(x);
def binary : 1 (x y) 0; # Low-precedence operator that ignores operands.
printd(123) : printd(456) : printd(789);
# Logical unary not.
def unary!(v)
if v then
0
else
1;
# Unary negate.
def unary-(v)
0-v;
# Define > with the same precedence as <.
def binary> 10 (LHS RHS)
RHS < LHS;
# Binary logical or, which does not short circuit.
def binary| 5 (LHS RHS)
if LHS then
1
else if RHS then
1
else
0;
# Binary logical and, which does not short circuit.
def binary& 6 (LHS RHS)
if !LHS then
0
else
!!RHS;
# Define = with slightly lower precedence than relationals.
def binary = 9 (LHS RHS)
!(LHS < RHS | LHS > RHS);
# Define ':' for sequencing: as a low-precedence operator that ignores operands
# and just returns the RHS.
def binary : 1 (x y) y;
extern putchard(char)
def printdensity(d)
if d > 8 then
putchard(32) # ' '
else if d > 4 then
putchard(46) # '.'
else if d > 2 then
putchard(43) # '+'
else
putchard(42); # '*'
printdensity(1): printdensity(2): printdensity(3):
printdensity(4): printdensity(5): printdensity(9):
putchard(10);
# Determine whether the specific location diverges.
# Solve for z = z^2 + c in the complex plane.
def mandleconverger(real imag iters creal cimag)
if iters > 255 | (real*real + imag*imag > 4) then
iters
else
mandleconverger(real*real - imag*imag + creal,
2*real*imag + cimag,
iters+1, creal, cimag);
# Return the number of iterations required for the iteration to escape
def mandleconverge(real imag)
mandleconverger(real, imag, 0, real, imag);
# Compute and plot the mandlebrot set with the specified 2 dimensional range
# info.
def mandelhelp(xmin xmax xstep ymin ymax ystep)
for y = ymin, y < ymax, ystep in (
(for x = xmin, x < xmax, xstep in
printdensity(mandleconverge(x,y)))
: putchard(10)
)
# mandel - This is a convenient helper function for plotting the mandelbrot set
# from the specified position with the specified Magnification.
def mandel(realstart imagstart realmag imagmag)
mandelhelp(realstart, realstart+realmag*78, realmag,
imagstart, imagstart+imagmag*40, imagmag);
mandel(-2.3, -1.3, 0.05, 0.07);
mandel(-2, -1, 0.02, 0.04);
mandel(-0.9, -1.4, 0.02, 0.03);