1 files changed, 79 insertions, 0 deletions
diff --git a/fnl/nvrc/macro/set.fnl b/fnl/nvrc/macro/set.fnl
new file mode 100644
index 0000000..144bdef
--- /dev/null
+++ b/fnl/nvrc/macro/set.fnl
@@ -0,0 +1,79 @@
+(local {: fn? : gensym-checksum : vlua} (require :nvrc.macro.toolkit))
+
+(fn str? [x]
+  (= :string (type x)))
+
+(fn ->str [x]
+  (tostring x))
+
+(fn nil? [x]
+  (= nil x))
+
+(fn includes? [xs x]
+  (accumulate [is? false _ v (ipairs xs) :until is?]
+    (= v x)))
+
+(lambda set! [name ?value]
+  "Set a vim option via the lua API.
+  The name of the option must a symbol.
+  If no value is specified, if the name begins with 'no' the value
+  becomes false, true otherwise."
+  (assert-compile (sym? name) "expected symbol for name" name)
+  (let [name (->str name)
+        value (or ?value (not (name:match "^no")))
+        name (or (name:match "^no(.+)$") name)]
+    (if (fn? value)
+      (let [vsym (gensym-checksum "__" value)]
+        `(do
+            (global ,vsym ,value)
+            (tset vim.opt ,name ,(vlua vsym))))
+      (match (name:sub -1)
+        "+" `(: (. vim.opt ,(name:sub 1 -2)) :append ,value)
+        "-" `(: (. vim.opt ,(name:sub 1 -2)) :remove ,value)
+        "^" `(: (. vim.opt ,(name:sub 1 -2)) :prepend ,value)
+        _ `(tset vim.opt ,name ,value)))))
+
+(lambda setl! [name ?value]
+  "Set a vim local option via the lua API.
+  The name of the option must a symbol.
+  If no value is specified, if the name begins with 'no' the value
+  becomes false, true otherwise."
+  (assert-compile (sym? name) "expected symbol for name" name)
+  (let [name (->str name)
+        value (or ?value
+                  (not (name:match "^no")))
+        name (or (name:match "^no(.+)$")
+                 name)]
+    (if (fn? value)
+      (let [fsym (gensym-checksum "__" value)]
+        `(do
+           (global ,fsym ,value)
+           (tset vim.opt_local ,name ,(vlua fsym))))
+      (match (name:sub -1)
+        :+ `(: (. vim.opt_local ,(name:sub 1 -2)) :append ,value)
+        :- `(: (. vim.opt_local ,(name:sub 1 -2)) :remove ,value)
+        :^ `(: (. vim.opt_local ,(name:sub 1 -2)) :prepend ,value)
+        _ `(tset vim.opt_local ,name ,value)))))
+
+(lambda setv! [name value]
+  "Set a vim variable via the lua API.
+  The name can be either a symbol or a string.
+  If the name begins with [gbwt] followed by [/:.], the name
+  is scoped to the respective scope."
+  (assert-compile (or (str? name) (sym? name))
+                  "expected string or symbol for name" name)
+  (let [name (->str name)
+        scope (when (includes? ["g/" "b/" "w/" "t/"
+                                "g." "b." "w." "t."
+                                "g:" "b:" "w:" "t:"] (name:sub 1 2))
+                (name:sub 1 1))
+        name (if
+               (nil? scope) name
+               (name:sub 3))]
+    `(tset ,(match scope
+              :b 'vim.b
+              :w 'vim.w
+              :t 'vim.t
+              _ 'vim.g) ,name ,value)))
+
+{: set! : setl! : setv!}