Changed . token to _dot

This change allows the dotfiles to work with chezmoi (e.g: on windows)
and improves grepability with neovim/telescope

dot_config/nushell/nu_scripts/modules/recursion/tree.nu

@@ -0,0 +1,54 @@
+# tree.nu: module for working with trees
+source typeof.nu #  Requires Nushell version 0.88 or later
+
+# A tree is a recursive data structure. In Nu, we take the view that any single atomic value
+# is a leaf. E.g. int, float, string, bool, etc.
+# Any structured data is some kind of a tree. E.g. list, record or table.
+
+
+
+
+
+
+
+# Applies closure to atomic data.
+def visit-scalar [act: closure] {
+  let data = $in
+  do $act $data
+}
+
+
+# Visit every element of list and apply  closure
+def visit-list [act: closure] {
+  let l = $in
+  $l |each {|x| $x | visit $act }
+}
+
+
+# Apply closure to every  column and value of record in input. Does a visit on
+# each key and then on each value.
+def visit-record [cl: closure] {
+items {|k, v| $k | visit $cl; $v | visit $cl }
+}
+
+
+
+
+# Applies closure to every row in table passed to input. Defers to visit-record
+# for each row.
+def visit-table [act: closure] {
+  each {|r| $r | visit-record $act }
+}
+
+
+# Applies closure to every node in tree passed to input recursively.
+def visit [act: closure] {
+    let stream = $in
+
+  match ($stream | typeof) {
+    'list' => { do $act 'list'; $stream | visit-list $act },
+    'record' => { do $act 'record'; $stream | visit-record $act },
+    'table' => { do $act 'table';  $stream | visit-table $act },
+    _ => { $stream | visit-scalar $act }
+  }
+}