Package: golang.org/x/mod/module

package module Import Path golang.org/x/mod/module (on go.dev) Dependency Relation imports 11 packages, and imported by one package

Involved Source Files d module.go Package module defines the module.Version type along with support code. The [module.Version] type is a simple Path, Version pair: type Version struct { Path string Version string } There are no restrictions imposed directly by use of this structure, but additional checking functions, most notably [Check], verify that a particular path, version pair is valid. # Escaped Paths Module paths appear as substrings of file system paths (in the download cache) and of web server URLs in the proxy protocol. In general we cannot rely on file systems to be case-sensitive, nor can we rely on web servers, since they read from file systems. That is, we cannot rely on the file system to keep rsc.io/QUOTE and rsc.io/quote separate. Windows and macOS don't. Instead, we must never require two different casings of a file path. Because we want the download cache to match the proxy protocol, and because we want the proxy protocol to be possible to serve from a tree of static files (which might be stored on a case-insensitive file system), the proxy protocol must never require two different casings of a URL path either. One possibility would be to make the escaped form be the lowercase hexadecimal encoding of the actual path bytes. This would avoid ever needing different casings of a file path, but it would be fairly illegible to most programmers when those paths appeared in the file system (including in file paths in compiler errors and stack traces) in web server logs, and so on. Instead, we want a safe escaped form that leaves most paths unaltered. The safe escaped form is to replace every uppercase letter with an exclamation mark followed by the letter's lowercase equivalent. For example, github.com/Azure/azure-sdk-for-go -> github.com/!azure/azure-sdk-for-go. github.com/GoogleCloudPlatform/cloudsql-proxy -> github.com/!google!cloud!platform/cloudsql-proxy github.com/Sirupsen/logrus -> github.com/!sirupsen/logrus. Import paths that avoid upper-case letters are left unchanged. Note that because import paths are ASCII-only and avoid various problematic punctuation (like : < and >), the escaped form is also ASCII-only and avoids the same problematic punctuation. Import paths have never allowed exclamation marks, so there is no need to define how to escape a literal !. # Unicode Restrictions Today, paths are disallowed from using Unicode. Although paths are currently disallowed from using Unicode, we would like at some point to allow Unicode letters as well, to assume that file systems and URLs are Unicode-safe (storing UTF-8), and apply the !-for-uppercase convention for escaping them in the file system. But there are at least two subtle considerations. First, note that not all case-fold equivalent distinct runes form an upper/lower pair. For example, U+004B ('K'), U+006B ('k'), and U+212A ('K' for Kelvin) are three distinct runes that case-fold to each other. When we do add Unicode letters, we must not assume that upper/lower are the only case-equivalent pairs. Perhaps the Kelvin symbol would be disallowed entirely, for example. Or perhaps it would escape as "!!k", or perhaps as "(212A)". Second, it would be nice to allow Unicode marks as well as letters, but marks include combining marks, and then we must deal not only with case folding but also normalization: both U+00E9 ('é') and U+0065 U+0301 ('e' followed by combining acute accent) look the same on the page and are treated by some file systems as the same path. If we do allow Unicode marks in paths, there must be some kind of normalization to allow only one canonical encoding of any character used in an import path. pseudo.go

/* one unexported ... *//* one unexported: */

Package-Level Variables (total 3, none are exported) /* 3 unexporteds ... *//* 3 unexporteds: */

Package-Level Constants (total 4, in which 1 is exported)

const PseudoVersionTimestampFormat = "20060102150405"

/* 3 unexporteds ... *//* 3 unexporteds: */