github.com/bingoohuang/gg@v0.0.0-20240325092523-45da7dee9335/pkg/man/english/words.go (about)

     1  // Package english provides utilities to generate more user-friendly English output.
     2  package english
     3  
     4  import (
     5  	"fmt"
     6  	"strings"
     7  
     8  	"github.com/bingoohuang/gg/pkg/man"
     9  )
    10  
    11  // These are included because they are common technical terms.
    12  var specialPlurals = map[string]string{
    13  	"index":  "indices",
    14  	"matrix": "matrices",
    15  	"vertex": "vertices",
    16  }
    17  
    18  var sibilantEndings = []string{"s", "sh", "tch", "x"}
    19  
    20  var isVowel = map[byte]bool{
    21  	'A': true, 'E': true, 'I': true, 'O': true, 'U': true,
    22  	'a': true, 'e': true, 'i': true, 'o': true, 'u': true,
    23  }
    24  
    25  // PluralWord builds the plural form of an English word.
    26  // The simple English rules of regular pluralization will be used
    27  // if the plural form is an empty string (i.e. not explicitly given).
    28  // The special cases are not guaranteed to work for strings outside ASCII.
    29  func PluralWord(quantity int, singular, plural string) string {
    30  	if quantity == 1 {
    31  		return singular
    32  	}
    33  	if plural != "" {
    34  		return plural
    35  	}
    36  	if plural = specialPlurals[singular]; plural != "" {
    37  		return plural
    38  	}
    39  
    40  	// We need to guess what the English plural might be.  Keep this
    41  	// function simple!  It doesn't need to know about every possiblity;
    42  	// only regular rules and the most common special cases.
    43  	//
    44  	// Reference: http://en.wikipedia.org/wiki/English_plural
    45  
    46  	for _, ending := range sibilantEndings {
    47  		if strings.HasSuffix(singular, ending) {
    48  			return singular + "es"
    49  		}
    50  	}
    51  	l := len(singular)
    52  	if l >= 2 && singular[l-1] == 'o' && !isVowel[singular[l-2]] {
    53  		return singular + "es"
    54  	}
    55  	if l >= 2 && singular[l-1] == 'y' && !isVowel[singular[l-2]] {
    56  		return singular[:l-1] + "ies"
    57  	}
    58  
    59  	return singular + "s"
    60  }
    61  
    62  // Plural formats an integer and a string into a single pluralized string.
    63  // The simple English rules of regular pluralization will be used
    64  // if the plural form is an empty string (i.e. not explicitly given).
    65  func Plural(quantity int, singular, plural string) string {
    66  	return fmt.Sprintf("%s %s", man.Comma(int64(quantity)), PluralWord(quantity, singular, plural))
    67  }
    68  
    69  // WordSeries converts a list of words into a word series in English.
    70  // It returns a string containing all the given words separated by commas,
    71  // the coordinating conjunction, and a serial comma, as appropriate.
    72  func WordSeries(words []string, conjunction string) string {
    73  	switch len(words) {
    74  	case 0:
    75  		return ""
    76  	case 1:
    77  		return words[0]
    78  	default:
    79  		return fmt.Sprintf("%s %s %s", strings.Join(words[:len(words)-1], ", "), conjunction, words[len(words)-1])
    80  	}
    81  }
    82  
    83  // OxfordWordSeries converts a list of words into a word series in English,
    84  // using an Oxford comma (https://en.wikipedia.org/wiki/Serial_comma). It
    85  // returns a string containing all the given words separated by commas, the
    86  // coordinating conjunction, and a serial comma, as appropriate.
    87  func OxfordWordSeries(words []string, conjunction string) string {
    88  	switch len(words) {
    89  	case 0:
    90  		return ""
    91  	case 1:
    92  		return words[0]
    93  	case 2:
    94  		return strings.Join(words, fmt.Sprintf(" %s ", conjunction))
    95  	default:
    96  		return fmt.Sprintf("%s, %s %s", strings.Join(words[:len(words)-1], ", "), conjunction, words[len(words)-1])
    97  	}
    98  }