wip iter-index, before change repr

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

diff --git a/templates/bigfloat.ts b/templates/bigfloat.ts
index 2bd16575eac64636a9c606d8ee2e6c4e05b3be58..ed3495661e64b04a75b89e4210bbd8bfa3046f98 100644 (file)
--- a/templates/bigfloat.ts
+++ b/templates/bigfloat.ts
@@ -71,6 +71,47 @@ class Bigfloat {
     this.exponent++;
   }
   
+  iter_incdec(stepsign: number): () => Bigfloat {
+    // stepsign should be roughly -1 or +1
+    let start = this.clone();
+    let i = this.exponent;
+    while (i < 0) {
+      start.extend_left();
+      i++;
+    }
+    while (start.limbs.length <= i) {
+      start.limb.push(0);
+    }
+    let delta = stepsign * 0x000001000000;
+    return function(){
+      for (;;) {
+       start.limbs[i] += delta;
+       let j=i;
+       for (;;) {
+         let new = Bigfloat.limb_mask(start_limbs[j]);
+         if (sstart_limbs[j] != new) {
+           start.limbs[j] = new;
+           j--;
+         } else if (j==0 &&
+                    (start_limbs[j] < Bigfoot.LIMB_NEGATIVE ||
+                     start_limbs[j] >= Bigfoot.LIMB_NEGATIVE))
+           
+                    
+           while (j<0) {
+             start.extend_left();
+             j++;
+           )
+           start.limbs[j] += Math.sign(stepsign);
+         } else {
+           
+         
+             
+           if (start_limbs[j] < Bigfloat.LIMB_MODULUS) 
+             
+       if (it>0 && start.limbs[it] > 
+    }
+  }
+
   iter_upto(endv: Bigfloat, count: number): () => Bigfloat {
     // next() can be called count times
     // to produce values > this, < endv