Path

Introduction

import 'path';

The path module builds file-system paths as strings. It uses \ on Windows and / on other platforms.

import 'path';
 
String file = path.join("build", "reports", "result.txt");
print(file);

Notes

• The module accepts / and \ as separators on all platforms.
• join and localize change only the path text. They do not check if an entry exists at the path.
• The fs module reads, writes, inspects, or deletes the entry at the path.
• userData is the only fallible function in the module. Its errors use path.ErrorCode codes. This is the same ErrorCode enum that fs uses.

path.getCwd()

String path.getCwd()

Returns the current working directory as an absolute path. Relative file-system paths start from this directory.

If the working directory cannot be read, this function causes a runtime error.

import 'path';
 
print(path.getCwd());       // /Users/you/project

path.join()

String path.join(String first, ...String more)

Joins one or more path parts with the separator of the platform and returns the result. It also removes repeated separators and . parts, and resolves .. where possible.

The function ignores empty parts. The result ends in a separator only when it is the root. A call to path.join() with no arguments is a compile error.

import 'path';
 
print(path.join("a", "b", "file.txt"));          // a/b/file.txt
print(path.join("/usr/local", "../bin", "nio")); // /usr/bin/nio
print(path.join("a//b", "./c"));                 // a/b/c
print(path.join("x", ".."));                     // .

path.localize()

String path.localize(String p)

Replaces each path separator with the separator of the platform and returns the result. It makes no other change to the path. It does not remove parts or resolve .., as join does.

import 'path';
 
print(path.localize("./thisdir/file"));
print(path.localize("a//b"));        // repeated separators are kept
print(path.localize("../up"));       // .. is kept

path.userData()

String path.userData(String app)

Returns the directory where the platform stores the data of an application named app. The app name is the last element of the path:

The function returns only the path. It does not create the directory. fs.createDir makes the directory the first time.

This is the only fallible function in the module. If the environment does not give the base location (for example, HOME is not set), it raises path.ErrorCode.NOT_FOUND. The app name must be one path element. An empty name, or a name that contains a separator, raises path.ErrorCode.INVALID.

import 'path';
import 'fs';
 
String? dir = path.userData("myapp") catch e {
    print(e.message);
};
if (dir != null && !fs.exists(dir)) {
    fs.createDir(dir) catch e { print(e.message); };
}