Test code examples in docs and add docs for per-file settings (#5474)

Signed-off-by: Nick Cameron <nrc@ncameron.org>

docs/kcl/index.md

@@ -6,9 +6,15 @@ layout: manual
 
 ## Table of Contents
 
-* [Types](kcl/types)
-* [Modules](kcl/modules)
-* [Known Issues](kcl/KNOWN-ISSUES)
+### Language
+
+* [`Types`](kcl/types)
+* [`Modules`](kcl/modules)
+* [`Settings`](kcl/settings)
+* [`Known Issues`](kcl/known-issues)
+
+### Standard library
+
 * **`std`**
   * [`HALF_TURN`](kcl/const_std-HALF_TURN)
   * [`QUARTER_TURN`](kcl/const_std-QUARTER_TURN)

docs/kcl/modules.md

@@ -20,7 +20,7 @@ export fn increment(x) {
 Other files in the project can now import functions that have been exported.
 This makes them available to use in another file.
 
-```
+```norun
 // main.kcl
 import increment from "util.kcl"
 
@@ -48,13 +48,13 @@ export fn decrement(x) {
 
 When importing, you can import multiple functions at once.
 
-```
+```norun
 import increment, decrement from "util.kcl"
 ```
 
 Imported symbols can be renamed for convenience or to avoid name collisions.
 
-```
+```norun
 import increment as inc, decrement as dec from "util.kcl"
 ```
 
@@ -63,13 +63,13 @@ import increment as inc, decrement as dec from "util.kcl"
 `import` can also be used to import files from other CAD systems. The format of the statement is the
 same as for KCL files. You can only import the whole file, not items from it. E.g.,
 
-```
+```norun
 import "tests/inputs/cube.obj"
 
 // Use `cube` just like a KCL object.
 ```
 
-```
+```norun
 import "tests/inputs/cube-2.sldprt" as cube
 
 // Use `cube` just like a KCL object.
@@ -78,7 +78,7 @@ import "tests/inputs/cube-2.sldprt" as cube
 You can make the file format explicit using a format attribute (useful if using a different
 extension), e.g.,
 
-```
+```norun
 @(format = obj)
 import "tests/inputs/cube"
 ```
@@ -87,7 +87,7 @@ For formats lacking unit data (such as STL, OBJ, or PLY files), the default
 unit of measurement is millimeters. Alternatively you may specify the unit
 by using an attirbute. Likewise, you can also specify a coordinate system. E.g.,
 
-```
+```norun
 @(unitLength = ft, coords = opengl)
 import "tests/inputs/cube.obj"
 ```

docs/kcl/settings.md

@@ -0,0 +1,30 @@
+---
+title: "KCL settings"
+excerpt: "Documentation of settings for the KCL language and Zoo Modeling App."
+layout: manual
+---
+
+# Per-file settings
+
+Settings which affect a single file are configured using the settings attribute.
+This must be at the top of the KCL file (comments before the attribute are permitted).
+E.g.,
+
+```
+// The settings attribute.
+@settings(defaultLengthUnit = in)
+
+// The rest of your KCL code goes below...
+
+x = 42 // Represents 42 inches.
+```
+
+The settings attribute may contain multiple properties separated by commas.
+Valid properties are:
+
+- `defaultLengthUnit`: the default length unit to use for numbers declared in this file.
+  - Accepted values: `mm`, `cm`, `m`, `in` (inches), `ft` (feet), `yd` (yards).
+- `defaultAngleUnit`: the default angle unit to use for numbers declared in this file.
+  - Accepted values: `deg` (degrees), `rad` (radians).
+
+These settings override any project-wide settings (configured in project.toml or via the UI).

docs/kcl/types.md

@@ -74,18 +74,15 @@ fn myFn(x) {
 
 As you can see above `myFn` just returns whatever it is given.
 
-KCL's early drafts used positional arguments, but we now use keyword arguments. If you declare a
-function like this:
+KCL's early drafts used positional arguments, but we now use keyword arguments:
 
 ```
+// If you declare a function like this
 fn add(left, right) {
   return left + right
 }
-```
 
-You can call it like this:
-
-```
+// You can call it like this:
 total = add(left = 1, right = 2)
 ```
 
@@ -111,14 +108,14 @@ three = add(1, delta = 2)
 
 It can be hard to read repeated function calls, because of all the nested brackets.
 
-```
+```norun
 i = 1
 x = h(g(f(i)))
 ```
 
 You can make this easier to read by breaking it into many declarations, but that is a bit annoying.
 
-```
+```norun
 i  = 1
 x0 = f(i)
 x1 = g(x0)
@@ -133,12 +130,12 @@ the `%` in the right-hand side.
 So, this means `x |> f(%) |> g(%)` is shorthand for `g(f(x))`. The code example above, with its
 somewhat-clunky `x0` and `x1` constants could be rewritten as
 
-```
+```norun
 i = 1
 x = i
-|> f(%)
-|> g(%)
-|> h(%)
+  |> f(%)
+  |> g(%)
+  |> h(%)
 ```
 
 This helps keep your code neat and avoid unnecessary declarations.
@@ -147,12 +144,12 @@ This helps keep your code neat and avoid unnecessary declarations.
 
 Say you have a long pipeline of sketch functions, like this:
 
-```
-startSketch()
-|> line(%, end = [3, 4])
-|> line(%, end = [10, 10])
-|> line(%, end = [-13, -14])
-|> close(%)
+```norun
+startSketchOn('XZ')
+  |> line(%, end = [3, 4])
+  |> line(%, end = [10, 10])
+  |> line(%, end = [-13, -14])
+  |> close(%)
 ```
 
 In this example, each function call outputs a sketch, and it gets put into the next function call via
@@ -162,12 +159,12 @@ If a function call uses an unlabeled first parameter, it will default to `%` if
 means that `|> line(%, end = [3, 4])` and `|> line(end = [3, 4])` are equivalent! So the above
 could be rewritten as 
 
-```
-startSketch()
-|> line(end = [3, 4])
-|> line(end = [10, 10])
-|> line(end = [-13, -14])
-|> close()
+```norun
+startSketchOn('XZ')
+ |> line(end = [3, 4])
+ |> line(end = [10, 10])
+ |> line(end = [-13, -14])
+ |> close()
 ```
 
 Note that we are still in the process of migrating KCL's standard library to use keyword arguments. So some
@@ -184,7 +181,7 @@ Tags are used to give a name (tag) to a specific path.
 The syntax for declaring a tag is `$myTag` you would use it in the following
 way:
 
-```
+```norun
 startSketchOn('XZ')
   |> startProfileAt(origin, %)
   |> angledLine({angle = 0, length = 191.26}, %, $rectangleSegmentA001)
@@ -216,7 +213,7 @@ use the tag `rectangleSegmentA001` in any function or expression in the file.
 
 However if the code was written like this:
 
-```
+```norun
 fn rect(origin) {
   return startSketchOn('XZ')
     |> startProfileAt(origin, %)
@@ -244,7 +241,7 @@ However you likely want to use those tags somewhere outside the `rect` function.
 Tags are accessible through the sketch group they are declared in.
 For example the following code works.
 
-```
+```norun
 fn rect(origin) {
   return startSketchOn('XZ')
     |> startProfileAt(origin, %)