Differences

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--- language:controlflow [2019/04/18 14:25]
rajit [Selections]
+++ language:controlflow [2022/05/13 08:45]
rajit
@@ Line 11: / Line 11: @@
 An example of the loop construct in ACT is shown below:
-<code>
+<code act>
 ( i : 10 : bool x[i..i]; )
 </code>
@@ Line 20: / Line 20: @@
 range ''0..9''. The body of the loop is the statement ''bool x[i..i];''. The effect of this statement is the same as
-<code>
+<code act>
 bool x[0..0];
 bool x[1..1];
@@ Line 31: / Line 31: @@
 is shown below:
-<code>
+<code act>
 register r[1..8];
 (i : 1..8 : r[i](in[i],out[i],control); )
@@ Line 48: / Line 48: @@
 command language.
-<code>
+<code act>
 pint i;
 i=0;
@@ Line 65: / Line 65: @@
 In production rule bodies, the loop
-<code>
+<code act>
 (&i:3: x[i])
 </code>
 expands to
-<code>
+<code act>
 x[0] & x[1] & x[2]
 </code>
@@ Line 82: / Line 82: @@
 syntax of a selection statement is:
-<code>
+<code act>
 [ boolean_expression -> body
 [] boolean_expression -> body
@@ Line 95: / Line 95: @@
 something special for register 0 as follows:
-<code>
+<code act>
 (i : 32 :
-    [ i = 0 -> r0(in[i],out[i],control)
+    [ i = 0 -> r0(in[i],out[i],control);
-   [] else -> r[i](in[i],out[i],control)
+   [] else -> r[i](in[i],out[i],control);
     ]
 )
@@ Line 110: / Line 110: @@
 the operators less than, less than or equal to, greater than, greater
 than or equal to, equal to, and not equal to respectively.
+===== Recursion =====
+Type definitions can be recursive. For instance, the following
+definition can be used to create a tree structure.
+<code act>
+template<pint N>
+defproc tree (bool a[N])
+{
+  [ N = 1 -> leaf l(a[0]);
+ [] N > 1 -> tree<N/2> t0(a[0..N/2-1]);
+             tree<N-N/2> t1(a[N/2..N-1]);
+  ]
+}
+</code>