Math operators (#1601)

* Add some math operations

* WIP for adding compound expressions

* precedence parsing

* paren expressions

* better lhs handling

* add compound comparisons and shorthand lefthand parsing

* Add or comparison and shorthand paths

crates/nu-cli/src/commands/autoview.rs

@@ -156,6 +156,12 @@ pub fn autoview(context: RunnableContext) -> Result<OutputStream, ShellError> {
                             } => {
                                 out!("{}", n);
                             }
+                            Value {
+                                value: UntaggedValue::Primitive(Primitive::Boolean(b)),
+                                ..
+                            } => {
+                                out!("{}", b);
+                            }
 
                             Value { value: UntaggedValue::Primitive(Primitive::Binary(ref b)), .. } => {
                                 if let Some(binary) = binary {

crates/nu-cli/src/commands/skip_while.rs

@@ -16,7 +16,7 @@ impl WholeStreamCommand for SkipWhile {
         Signature::build("skip-while")
             .required(
                 "condition",
-                SyntaxShape::Condition,
+                SyntaxShape::Math,
                 "the condition that must be met to continue skipping",
             )
             .filter()

crates/nu-cli/src/commands/where_.rs

@@ -18,7 +18,7 @@ impl PerItemCommand for Where {
     fn signature(&self) -> Signature {
         Signature::build("where").required(
             "condition",
-            SyntaxShape::Condition,
+            SyntaxShape::Math,
             "the condition that must match",
         )
     }