add write functionality to ParamFile

1 files changed, 37 insertions, 0 deletions

diff --git a/nerv.lua b/nerv.lua
index 33b1aff..1c4ba39 100644
--- a/nerv.lua
+++ b/nerv.lua
@@ -1,5 +1,6 @@
 require 'libnerv'
 require 'matrix.init'
+require 'io.init'
 -- nerv.class = require 'pl.class'
 nerv.utils = require 'pl.utils'
 
@@ -35,3 +36,39 @@ function nerv.class(tname, parenttname)
    end
    return mt, mpt
 end
+
+function table.val_to_str(v)
+  if "string" == type(v) then
+    v = string.gsub(v, "\n", "\\n")
+    if string.match(string.gsub(v,"[^'\"]",""), '^"+$') then
+      return "'" .. v .. "'"
+    end
+    return '"' .. string.gsub(v,'"', '\\"') .. '"'
+  else
+    return "table" == type(v) and table.tostring(v) or
+      tostring(v)
+  end
+end
+
+function table.key_to_str (k)
+  if "string" == type(k) and string.match(k, "^[_%a][_%a%d]*$") then
+    return k
+  else
+    return "[" .. table.val_to_str(k) .. "]"
+  end
+end
+
+function table.tostring(tbl)
+  local result, done = {}, {}
+  for k, v in ipairs(tbl) do
+    table.insert(result, table.val_to_str(v))
+    done[k] = true
+  end
+  for k, v in pairs(tbl) do
+    if not done[k] then
+      table.insert(result,
+        table.key_to_str(k) .. "=" .. table.val_to_str(v))
+    end
+  end
+  return "{" .. table.concat(result, ",") .. "}"
+end