# Nix path builtins

• isPath e - true if e is a path, otherwise false
• path args -
• pathExists path - true if path exists at evaluation time, otherwise false
• placeholder output - return a placeholder string for output that will be substituted with the actual output path at build time
• readDir path - return the contents of the directory at path as a set with file names as keys and as values
• readFile path - contents of path as a string