do loop.

doc/src/language/do.md

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+`do` Loop
+=========
+
+{{#include ../links.md}}
+
+`do` loops have two opposite variants: `do` ... `while` and `do` ... `until`.
+
+Like the `while` loop, `continue` can be used to skip to the next iteration, by-passing all following statements;
+`break` can be used to break out of the loop unconditionally.
+
+```rust
+let x = 10;
+
+do {
+    x -= 1;
+    if x < 6 { continue; }  // skip to the next iteration
+    print(x);
+    if x == 5 { break; }    // break out of do loop
+} while x > 0;
+
+
+do {
+    x -= 1;
+    if x < 6 { continue; }  // skip to the next iteration
+    print(x);
+    if x == 5 { break; }    // break out of do loop
+} until x == 0;
+```