pkgs/Profpatsch/nman: allow any absolute or relative paths for -f

This should pass the right kinds of path to nix in most situations.

Author: Profpatsch

pkgs/profpatsch/nman/nman.1

@@ -93,11 +93,7 @@ Use the specified .nix file
 instead of
 .Ql <nixpkgs>
 from the Nix search path. This allows using local package definitions
-or custom package sets. Use
-.Dq .\&
-to refer to
-.Pa ./default.nix
-in the current directory.
+or custom package sets.
 .El
 
 .Sh EXAMPLES

pkgs/profpatsch/nman/nman.rs

@@ -342,10 +342,12 @@ impl Main {
         let tmpdir = TempDir::new("nman").map_err(NmanError::IO)?;
         let nix_import = match &self.file_path {
             Some(path) => {
-                if path == "." {
-                    "./default.nix".to_string()
+                if path.starts_with('/') {
+                    // Absolute path - strip trailing slashes
+                    path.trim_end_matches('/').to_string()
                 } else {
-                    path.clone()
+                    // Relative path - prepend ./
+                    format!("./{}", path)
                 }
             },
             None => "<nixpkgs>".to_string(),