docs: update todos

extensions/ext-computing/docs/README.md

@@ -0,0 +1,26 @@
+# Computing
+
+library: [fasteval](https://github.com/likebike/fasteval)
+
+```rust
+fn main() -> Result<(), fasteval::Error> {
+    // This example doesn't use any variables, so just use an EmptyNamespace:
+    let mut ns = fasteval::EmptyNamespace;
+
+    let val = fasteval::ez_eval(
+        "1+2*3/4^5%6 + log(100K) + log(e(),100) + [3*(3-3)/3] + (2<3) && 1.23",    &mut ns)?;
+    //    |            |      |    |   |          |               |   |
+    //    |            |      |    |   |          |               |   boolean logic with short-circuit support
+    //    |            |      |    |   |          |               comparisons
+    //    |            |      |    |   |          square-brackets act like parenthesis
+    //    |            |      |    |   built-in constants: e(), pi()
+    //    |            |      |    'log' can take an optional first 'base' argument, defaults to 10
+    //    |            |      numeric literal with suffix: p, n, µ, m, K, M, G, T
+    //    |            many built-in functions: print, int, ceil, floor, abs, sign, log, round, min, max, sin, asin, ...
+    //    standard binary operators
+
+    assert_eq!(val, 1.23);
+
+    Ok(())
+}
+```