Ben / Nujel

;; Nujel - Copyright (C) 2020-2021 - Benjamin Vincent Schulenburg
;; This project uses the MIT license, a copy should be included under /LICENSE
;;
;; Introspection and procedures returning info about the runtime

[defn display/error/wrap [i text]
      [case i
            [0 [ansi-red text]]
            [1 [string text]]
            [2 [ansi-yellow [string/write text]]]
            [3 [describe/closure text]]
            [otherwise text]]]

[defn display/error/iter [error i]
      [if error
          [cons [display/error/wrap i [car error]]
                [display/error/iter [cdr error] [+ 1 i]]]
          [cons "" #nil]]]

[defn display/error [error]
      "Display ERROR in a nice, human readable way"
      [display [join [display/error/iter error 0] "\r\n"]]]

[defn closure/documentation [o]
      [meta o :documentation]]

[defn describe/thing [o]
      "Describe a specific value O"
      [def documentation [closure/documentation o]]
      [def arguments [closure/arguments o]]
      [fmt "{arguments:?} - {documentation}"]]

[defn describe/string [a]
      "Descibe whatever value string A resolves to"
      [describe/thing [resolve [string->symbol a]]]]

[defn describe [fun] "Describe FUN, if there is documentation available"
      [if [string? fun]
          [describe/string fun]
          [describe/thing fun]]]

[defn symbol-table [off len environment]
      "Return a list of LEN symbols defined in ENVIRONMENT starting at OFF"
      [when-not environment [set! environment root-closure]]
      [when-not off [set! off 0]]
      [when-not len [set! len 9999999]]
      [sublist [eval-in environment '[symbol-table*]] off [+ off len] #nil]]

[def gensym/counter 0]
[defn gensym [prefix]
      [++ gensym/counter]
      [string->symbol [cat prefix "ΓεnΣym-" gensym/counter]]]

[def root-closure [current-closure]]