Minor improvements (#6)

* Various minor improvements

These include:
- Some protection against infinite loops, e.g. with metatables
- Reporting on Doc objects (the value is shown within '|' characters)
- Showing array sizes

* Update docs and examples to match the latest

Author: wlupton

README.md

@@ -30,9 +30,9 @@ text
 
 ```text
 (#) pandoc Pandoc {
-  blocks: Blocks {
+  blocks: Blocks[1] {
     [1] Para {
-      content: Inlines {
+      content: Inlines[1] {
         [1] Str "text"
       }
     }
@@ -66,14 +66,14 @@ end
 ```text
 % pandoc simple.md -L para.lua >/dev/null --verbose
 [INFO] Running filter para.lua
-(I) para Para {content: Inlines {[1] Str "text"}}
-[INFO] Completed filter para.lua in 8 ms
+(I) para Para {content: Inlines[1] {[1] Str "text"}}
+[INFO] Completed filter para.lua in 7 ms
 ```
 
 All lua objects can be passed to `logging.info()` etc., and they will be output in a form that should be useful for lua filter development and debugging. The output is intended to be a faithful representation of the [pandoc lua types](https://pandoc.org/lua-filters.html#module-pandoc) and should make it easy to "dig down". For example, you can see that:
 
 * `para` is a [Para](https://pandoc.org/lua-filters.html#type-para) instance
-* `para.content` is an [Inlines](https://pandoc.org/lua-filters.html#type-inlines) instance
+* `para.content` is an [Inlines](https://pandoc.org/lua-filters.html#type-inlines) instance with a single element
 * `para.content[1]` is a [Str](https://pandoc.org/lua-filters.html#type-str) instance
 * `para.content[1].text` is a string
 
@@ -95,14 +95,14 @@ end
 ```text
 % pandoc simple.md -L para2.lua >/dev/null --verbose
 [INFO] Running filter para2.lua
-(I) para Para {content: Inlines {[1] Str "text"}}
-(I) para.content Inlines {[1] Str "text"}
+(I) para Para {content: Inlines[1] {[1] Str "text"}}
+(I) para.content Inlines[1] {[1] Str "text"}
 (I) para.content[1] Str "text"
 (I) para.content[1].text text
-[INFO] Completed filter para2.lua in 8 ms
+[INFO] Completed filter para2.lua in 7 ms
 ```
 
-Why is the last `text` not quoted?
+The last `text` is not quoted, because lua strings are always output literally.
 
 # Module contents
 

examples/dumpex.lua.expected

@@ -4,11 +4,22 @@ false
 "string"
 "Here’s a non-ASCII character."
 {}
-{[1] 1, [2] 2, [3] 3}
+[3] {[1] 1, [2] 2, [3] 3}
 {a: 1, b: 2, c: 3}
-{[1] 4, [2] 5, a: 1, b: 2, c: 3}
-{[1] 4, [2] 5, [3] 6, [4] 7, [5] 8, [6] 9, [7] 10, a: 1, b: 2, c: 3}
-{
+[2] {[1] 4, [2] 5, a: 1, b: 2, c: 3}
+[7] {
+  [1] 4
+  [2] 5
+  [3] 6
+  [4] 7
+  [5] 8
+  [6] 9
+  [7] 10
+  a: 1
+  b: 2
+  c: 3
+}
+[8] {
   [1] 4
   [2] 5
   [3] 6
@@ -21,10 +32,10 @@ false
   b: 2
   c: 3
 }
-{
+[3] {
   [1] 1
   [2] 2
-  [3] {
+  [3] [3] {
     [1] 3
     [2] 4
     [3] {

examples/levels.lua.expected

@@ -2,8 +2,8 @@
 (E) this is output if loglevel >= -1
 (W) this is output if loglevel >= 0
 (#) args are automatically separated with spaces and a newline is added if necessary
-(#) args can be of any type, e.g. {maps: "like", this: "one"} or {[1] "lists", [2] "like", [3] "this", [4] "one"}
-(#) if an arg is too long it will be output on multiple lines {
+(#) args can be of any type, e.g. {maps: "like", this: "one"} or [4] {[1] "lists", [2] "like", [3] "this", [4] "one"}
+(#) if an arg is too long it will be output on multiple lines [5] {
   [1] "aardvark"
   [2] "bison"
   [3] "camel"

examples/para.lua.expected

@@ -1,6 +1,6 @@
 [INFO] Running filter para.lua
 (I) para Para {
-  content: Inlines {
+  content: Inlines[29] {
     [1] Str "This"
     [2] Space
     [3] Str "directory"
@@ -33,7 +33,7 @@
   }
 }
 (I) para Para {
-  content: Inlines {
+  content: Inlines[25] {
     [1] Str "These"
     [2] Space
     [3] Str "files"
@@ -62,7 +62,7 @@
   }
 }
 (I) para Para {
-  content: Inlines {
+  content: Inlines[37] {
     [1] Str "There’s"
     [2] Space
     [3] Str "also"
@@ -110,28 +110,28 @@
   }
 }
 (I) para Para {
-  content: Inlines {
+  content: Inlines[11] {
     [1] Str "Paragraph"
     [2] Space
     [3] Str "with"
     [4] Space
     [5] Emph {
-      content: Inlines {
+      content: Inlines[1] {
         [1] Str "emphasized"
       }
     }
     [6] Space
     [7] Str "and"
     [8] Space
     [9] Strong {
-      content: Inlines {
+      content: Inlines[1] {
         [1] Str "bold"
       }
     }
     [10] Space
     [11] Str "text."
   }
 }
-(I) para Para {content: Inlines {[1] Str "text"}}
-(I) para Para {content: Inlines {[1] Str "smart-quote-’"}}
+(I) para Para {content: Inlines[1] {[1] Str "text"}}
+(I) para Para {content: Inlines[1] {[1] Str "smart-quote-’"}}
 [INFO] Completed filter para.lua in NN ms

examples/para2.lua.expected

@@ -1,6 +1,6 @@
 [INFO] Running filter para2.lua
 (I) para Para {
-  content: Inlines {
+  content: Inlines[29] {
     [1] Str "This"
     [2] Space
     [3] Str "directory"
@@ -32,7 +32,7 @@
     [29] Str "files."
   }
 }
-(I) para.content Inlines {
+(I) para.content Inlines[29] {
   [1] Str "This"
   [2] Space
   [3] Str "directory"
@@ -66,7 +66,7 @@
 (I) para.content[1] Str "This"
 (I) para.content[1].text This
 (I) para Para {
-  content: Inlines {
+  content: Inlines[25] {
     [1] Str "These"
     [2] Space
     [3] Str "files"
@@ -94,7 +94,7 @@
     [25] Str "file."
   }
 }
-(I) para.content Inlines {
+(I) para.content Inlines[25] {
   [1] Str "These"
   [2] Space
   [3] Str "files"
@@ -124,7 +124,7 @@
 (I) para.content[1] Str "These"
 (I) para.content[1].text These
 (I) para Para {
-  content: Inlines {
+  content: Inlines[37] {
     [1] Str "There’s"
     [2] Space
     [3] Str "also"
@@ -171,7 +171,7 @@
     [37] Str "output."
   }
 }
-(I) para.content Inlines {
+(I) para.content Inlines[37] {
   [1] Str "There’s"
   [2] Space
   [3] Str "also"
@@ -220,43 +220,43 @@
 (I) para.content[1] Str "There’s"
 (I) para.content[1].text There’s
 (I) para Para {
-  content: Inlines {
+  content: Inlines[11] {
     [1] Str "Paragraph"
     [2] Space
     [3] Str "with"
     [4] Space
     [5] Emph {
-      content: Inlines {
+      content: Inlines[1] {
         [1] Str "emphasized"
       }
     }
     [6] Space
     [7] Str "and"
     [8] Space
     [9] Strong {
-      content: Inlines {
+      content: Inlines[1] {
         [1] Str "bold"
       }
     }
     [10] Space
     [11] Str "text."
   }
 }
-(I) para.content Inlines {
+(I) para.content Inlines[11] {
   [1] Str "Paragraph"
   [2] Space
   [3] Str "with"
   [4] Space
   [5] Emph {
-    content: Inlines {
+    content: Inlines[1] {
       [1] Str "emphasized"
     }
   }
   [6] Space
   [7] Str "and"
   [8] Space
   [9] Strong {
-    content: Inlines {
+    content: Inlines[1] {
       [1] Str "bold"
     }
   }
@@ -265,12 +265,12 @@
 }
 (I) para.content[1] Str "Paragraph"
 (I) para.content[1].text Paragraph
-(I) para Para {content: Inlines {[1] Str "text"}}
-(I) para.content Inlines {[1] Str "text"}
+(I) para Para {content: Inlines[1] {[1] Str "text"}}
+(I) para.content Inlines[1] {[1] Str "text"}
 (I) para.content[1] Str "text"
 (I) para.content[1].text text
-(I) para Para {content: Inlines {[1] Str "smart-quote-’"}}
-(I) para.content Inlines {[1] Str "smart-quote-’"}
+(I) para Para {content: Inlines[1] {[1] Str "smart-quote-’"}}
+(I) para.content Inlines[1] {[1] Str "smart-quote-’"}
 (I) para.content[1] Str "smart-quote-’"
 (I) para.content[1].text smart-quote-’
 [INFO] Completed filter para2.lua in NN ms