Function std.path.isValidPath

Generally, this function checks that path is not empty, and that each component of the path either satisfies isValidFilename or is equal to "." or "..". It does not check whether the path points to an existing file or directory; use std.file.exists for this purpose.

On Windows, some special rules apply:

• If the second character of path is a colon (':'), the first character is interpreted as a drive letter, and must be in the range A-Z (case insensitive).
• If path is on the form \\$(I server)\$(I share)\... (UNC path), isValidFilename is applied to server and share as well.
• If path starts with \\?\ (long UNC path), the only requirement for the rest of the string is that it does not contain the null character.
• If path starts with \\.\ (Win32 device namespace) this function returns false; such paths are beyond the scope of this module.

Prototype

bool isValidPath(Range)(
  Range path
)
if (is(StringTypeOf!Range) || isRandomAccessRange!Range && hasLength!Range && hasSlicing!Range && isSomeChar!(ElementEncodingType!Range));

Parameters

Returns

true if path is a valid path.

Example

assert (isValidPath("/foo/bar"));
assert (!isValidPath("/foo\0/bar"));
assert (isValidPath("/"));
assert (isValidPath("a"));

version (Windows)
{
    assert (isValidPath(c:\));
    assert (isValidPath(c:\foo));
    assert (isValidPath(c:\foo\.\bar\\\..\));
    assert (!isValidPath(!:\foo));
    assert (!isValidPath(c::\foo));
    assert (!isValidPath(c:\foo?));
    assert (!isValidPath(c:\foo.));

    assert (isValidPath(\\server\share));
    assert (isValidPath(\\server\share\foo));
    assert (isValidPath(\\server\share\\foo));
    assert (!isValidPath(\\\server\share\foo));
    assert (!isValidPath(\\server\\share\foo));
    assert (!isValidPath(\\ser*er\share\foo));
    assert (!isValidPath(\\server\sha?e\foo));
    assert (!isValidPath(\\server\share\|oo));

    assert (isValidPath(\\?\<>:"?*|/\..\.));
    assert (!isValidPath("\\\\?\\foo\0bar"));

    assert (!isValidPath(\\.\PhysicalDisk1));
    assert (!isValidPath(\\));
}

import std.utf : byCodeUnit;
assert (isValidPath("/foo/bar".byCodeUnit));
}




/** Performs tilde expansion in paths on POSIX systems.
On Windows, this function does nothing.

There are two ways of using tilde expansion in a path. One
involves using the tilde alone or followed by a path separator. In
this case, the tilde will be expanded with the value of the
environment variable HOME.  The second way is putting
a username after the tilde (i.e. ~john/Mail). Here,
the username will be searched for in the user database
(i.e. /etc/passwd on Unix systems) and will expand to
whatever path is stored there.  The username is considered the
string after the tilde ending at the first instance of a path
separator.

Note that using the ~user syntax may give different
values from just ~ if the environment variable doesn't
match the value stored in the user database.

When the environment variable version is used, the path won't
be modified if the environment variable doesn't exist or it
is empty. When the database version is used, the path won't be
modified if the user doesn't exist in the database or there is
not enough memory to perform the query.

This function performs several memory allocations.

Params:
    inputPath = The path name to expand.

Returns:
inputPath with the tilde expanded, or just inputPath
if it could not be expanded.
For Windows, expandTilde merely returns its argument inputPath.

Examples:

void processFile(string path) { // Allow calling this function with paths such as ~/foo auto fullPath = expandTilde(path); ...