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Separators and Styles ​

The Path module supports POSIX, Windows, and native path styles. This matters because Vix can run on one platform while preparing paths for another. A command running on Linux may still need to generate Windows-style paths, and a project tool may want stable POSIX output even when it is executed on Windows.

For normal use, include the public header:

cpp
#include <vix/path.hpp>

All public APIs live in the vix::path namespace.

Path styles ​

PathStyle controls the syntax rules used by path operations.

cpp
enum class PathStyle
{
  Native,
  Posix,
  Windows
};

PathStyle::Native follows the platform where the program is running. PathStyle::Posix uses POSIX-style output and prefers /. PathStyle::Windows uses Windows-style output and prefers \.

cpp
vix::path::PathOptions options;
options.style = vix::path::PathStyle::Posix;

Choosing the style explicitly is usually better in tooling code. It makes the expected output clear and avoids accidental differences between machines.

Preferred separator ​

Use preferred_separator() when code needs the separator character for a style.

cpp
char sep = vix::path::preferred_separator(
  vix::path::PathStyle::Posix
);

// sep == '/'
cpp
char sep = vix::path::preferred_separator(
  vix::path::PathStyle::Windows
);

// sep == '\\'

For PathStyle::Native, the result depends on the current platform.

cpp
char sep = vix::path::preferred_separator(
  vix::path::PathStyle::Native
);

This helper is useful when a caller needs to build a small display string or align custom logic with the same separator style used by join() and normalize().

Recognized separators ​

The module recognizes both / and \ as separators during lexical processing.

cpp
bool slash = vix::path::is_separator('/');
// slash == true
cpp
bool backslash = vix::path::is_separator('\\');
// backslash == true

A normal character is not a separator.

cpp
bool regular = vix::path::is_separator('x');
// regular == false

Recognizing both separator characters makes the module tolerant when reading path strings. The selected style still controls which separator is preferred in generated output.

Leading and trailing separators ​

Use has_leading_separator() to check whether a path starts with a separator.

cpp
bool leading = vix::path::has_leading_separator("/tmp");

// leading == true

Use has_trailing_separator() to check whether a path ends with a separator.

cpp
bool trailing = vix::path::has_trailing_separator("/tmp/");

// trailing == true
cpp
bool trailing = vix::path::has_trailing_separator("/tmp/file.txt");

// trailing == false

These helpers are simple lexical checks. They do not inspect the filesystem and they do not decide whether the path is a directory.

POSIX style ​

POSIX style uses / as the preferred separator. A path starting with a separator is treated as absolute.

cpp
bool absolute = vix::path::is_absolute(
  "/usr/bin",
  vix::path::PathStyle::Posix
);

// absolute == true

A path without a leading separator is relative.

cpp
bool relative = vix::path::is_relative(
  "usr/bin",
  vix::path::PathStyle::Posix
);

// relative == true

When POSIX style is used with join() or normalize(), generated output uses /.

cpp
vix::path::PathOptions options;
options.style = vix::path::PathStyle::Posix;

auto joined = vix::path::join("/usr/", "/bin", options);

if (!joined) {
  return joined.error();
}

// joined.value() == "/usr/bin"

Windows style ​

Windows style uses \ as the preferred separator. The module recognizes drive-root paths such as C:\Windows.

cpp
bool absolute = vix::path::is_absolute(
  "C:\\Windows",
  vix::path::PathStyle::Windows
);

// absolute == true

It also recognizes UNC-style paths.

cpp
bool absolute = vix::path::is_absolute(
  "\\\\server\\share",
  vix::path::PathStyle::Windows
);

// absolute == true

A path without a Windows root is relative.

cpp
bool relative = vix::path::is_relative(
  "docs\\readme.md",
  vix::path::PathStyle::Windows
);

// relative == true

When Windows style is selected, join() and normalize() produce Windows-style output.

cpp
vix::path::PathOptions options;
options.style = vix::path::PathStyle::Windows;

auto joined = vix::path::join(
  "C:\\Users\\",
  "\\gaspard",
  options
);

if (!joined) {
  return joined.error();
}

// joined.value() == "C:\\Users\\gaspard"

Native style ​

PathStyle::Native follows the platform where the program is compiled and executed.

cpp
vix::path::PathOptions options;
options.style = vix::path::PathStyle::Native;

This is useful when the path should match the current machine. It is less useful for generated project files, cross-platform manifests, or documentation examples where the expected output should be the same everywhere.

For stable tooling behavior, prefer PathStyle::Posix or PathStyle::Windows when the target format is known.

Separator conversion through normalization ​

Normalization can read mixed separators and rebuild the path with the preferred separator for the selected style.

cpp
vix::path::PathOptions options;
options.style = vix::path::PathStyle::Posix;

auto path = vix::path::normalize(
  "src\\core//main.cpp",
  options
);

if (!path) {
  return path.error();
}

// path.value() == "src/core/main.cpp"

With Windows style, the generated output uses \.

cpp
vix::path::PathOptions options;
options.style = vix::path::PathStyle::Windows;

auto path = vix::path::normalize(
  "C:/temp//foo\\bar",
  options
);

if (!path) {
  return path.error();
}

// path.value() == "C:\\temp\\foo\\bar"

This is one of the reasons the style belongs in PathOptions. The same input string can be normalized into different output forms depending on the target syntax.

Repeated separators ​

By default, repeated separators are collapsed during normalization.

cpp
vix::path::PathOptions options;
options.style = vix::path::PathStyle::Posix;

auto path = vix::path::normalize(
  "/a//b///c",
  options
);

if (!path) {
  return path.error();
}

// path.value() == "/a/b/c"

This keeps generated paths clean and avoids carrying accidental separator noise from user input, configuration files, or string concatenation.

Trailing separators ​

By default, normalization does not preserve a trailing separator.

cpp
vix::path::PathOptions options;
options.style = vix::path::PathStyle::Posix;

auto path = vix::path::normalize(
  "build/generated/",
  options
);

if (!path) {
  return path.error();
}

// path.value() == "build/generated"

Set preserve_trailing_separator when the trailing separator should remain part of the output representation.

cpp
vix::path::PathOptions options;
options.style = vix::path::PathStyle::Posix;
options.preserve_trailing_separator = true;

auto path = vix::path::normalize(
  "build/generated/",
  options
);

if (!path) {
  return path.error();
}

// path.value() == "build/generated/"

This option preserves a trailing separator only when the input already had one. It does not add a separator to a path that did not end with one.

Style and roots ​

The selected style also affects how roots are understood. In POSIX style, / is the main root form.

cpp
bool root = vix::path::is_absolute(
  "/project",
  vix::path::PathStyle::Posix
);

// root == true

In Windows style, drive-root paths and UNC-style paths are recognized.

cpp
bool drive = vix::path::is_absolute(
  "C:\\project",
  vix::path::PathStyle::Windows
);

// drive == true
cpp
bool unc = vix::path::is_absolute(
  "\\\\server\\share",
  vix::path::PathStyle::Windows
);

// unc == true

Roots matter most when computing relative paths. A relative path can only be computed when the target and base have compatible roots.

cpp
vix::path::PathOptions options;
options.style = vix::path::PathStyle::Windows;

auto rel = vix::path::relative(
  "D:\\docs\\file.txt",
  "C:\\base",
  options
);

if (!rel) {
  // incompatible roots
}

When incompatible roots are acceptable and the caller still wants a usable path, use lexically_proximate() instead.

A practical style workflow ​

The following example normalizes the same conceptual path for POSIX and Windows output.

cpp
#include <iostream>
#include <vix/path.hpp>

int main()
{
  vix::path::PathOptions posix;
  posix.style = vix::path::PathStyle::Posix;

  auto a = vix::path::normalize(
    "src\\core//main.cpp",
    posix
  );

  if (!a) {
    std::cerr << a.error().message() << '\n';
    return 1;
  }

  vix::path::PathOptions windows;
  windows.style = vix::path::PathStyle::Windows;

  auto b = vix::path::normalize(
    "src\\core//main.cpp",
    windows
  );

  if (!b) {
    std::cerr << b.error().message() << '\n';
    return 1;
  }

  std::cout << "posix: " << a.value() << '\n';
  std::cout << "windows: " << b.value() << '\n';

  return 0;
}

The input path is only text. The selected style decides how that text is interpreted and rebuilt.

Practical rule ​

Use explicit styles when the output format matters. Use POSIX for project metadata, generated documentation examples, or portable internal paths. Use Windows when generating or validating Windows-style paths. Use Native only when the path should follow the machine running the code.

The next page explains PathOptions in detail.

Released under the MIT License.

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