github.com/graybobo/golang.org-package-offline-cache@v0.0.0-20200626051047-6608995c132f/x/text/encoding/ianaindex/ianaindex.go (about)

     1  // Copyright 2015 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // Package ianaindex maps names to Encodings as specified by the IANA registry.
     6  // This includes both the MIME and IANA names.
     7  //
     8  // See http://www.iana.org/assignments/character-sets/character-sets.xhtml for
     9  // more details.
    10  package ianaindex
    11  
    12  import (
    13  	"golang.org/x/text/encoding"
    14  )
    15  
    16  // TODO: allow users to specify their own aliases?
    17  // TODO: allow users to specify their own indexes?
    18  // TODO: allow canonicalizing names
    19  
    20  // NOTE: only use these top-level variables if we can get the linker to drop
    21  // the indexes when they are not used. Make them a function or perhaps only
    22  // support MIME otherwise.
    23  
    24  var (
    25  	// MIME is an index to map MIME names. It does not support aliases.
    26  	MIME *Index
    27  
    28  	// IANA is an index that supports all names and aliases using IANA names as
    29  	// the canonical identifier.
    30  	IANA *Index
    31  )
    32  
    33  // Index maps names registered by IANA to Encodings.
    34  type Index struct {
    35  }
    36  
    37  // Get returns an Encoding for IANA-registered names. Matching is
    38  // case-insensitive.
    39  func (x *Index) Get(name string) (encoding.Encoding, error) {
    40  	panic("TODO: implement")
    41  }
    42  
    43  // Name reports the canonical name of the given Encoding. It will return an
    44  // error if the e is not associated with a known encoding scheme.
    45  func (x *Index) Name(e encoding.Encoding) (string, error) {
    46  	panic("TODO: implement")
    47  }
    48  
    49  // TODO: the coverage of this index is rather spotty. Allowing users to set
    50  // encodings would allow:
    51  // - users to increase coverage
    52  // - allow a partially loaded set of encodings in case the user doesn't need to
    53  //   them all.
    54  // - write an OS-specific wrapper for supported encodings and set them.
    55  // The exact definition of Set depends a bit on if and how we want to let users
    56  // write their own Encoding implementations. Also, it is not possible yet to
    57  // only partially load the encodings without doing some refactoring. Until this
    58  // is solved, we might as well not support Set.
    59  // // Set sets the e to be used for the encoding scheme identified by name. Only
    60  // // canonical names may be used. An empty name assigns e to its internally
    61  // // associated encoding scheme.
    62  // func (x *Index) Set(name string, e encoding.Encoding) error {
    63  // 	panic("TODO: implement")
    64  // }