github.com/dolthub/dolt/go@v0.40.5-0.20240520175717-68db7794bea6/libraries/utils/strhelp/string_help.go (about)

     1  // Copyright 2019 Dolthub, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package strhelp
    16  
    17  import (
    18  	"fmt"
    19  	"strconv"
    20  	"strings"
    21  )
    22  
    23  // NthToken returns the Nth token in s, delimited by delim. There is always at least one token: the zeroth token is the
    24  // input string if delim doesn't occur in s. The second return value will be false if there is no Nth token.
    25  func NthToken(s string, delim rune, n int) (string, bool) {
    26  	if n < 0 {
    27  		panic("invalid arguments.")
    28  	}
    29  
    30  	prev := 0
    31  	curr := 0
    32  	for ; curr < len(s); curr++ {
    33  		if s[curr] == uint8(delim) {
    34  			n--
    35  
    36  			if n >= 0 {
    37  				prev = curr + 1
    38  			} else {
    39  				break
    40  			}
    41  		}
    42  	}
    43  
    44  	if n <= 0 && prev <= curr {
    45  		return s[prev:curr], true
    46  	}
    47  
    48  	return "", false
    49  }
    50  
    51  func CommaIfy(n int64) string {
    52  	str := strconv.FormatInt(n, 10)
    53  
    54  	if len(str) < 4 {
    55  		return str
    56  	}
    57  
    58  	result := ""
    59  
    60  	for i := len(str); i >= 0; i -= 3 {
    61  		if i-4 >= 0 {
    62  			result = "," + str[i-3:i] + result
    63  		} else {
    64  			result = str[0:i] + result
    65  		}
    66  	}
    67  
    68  	return result
    69  }
    70  
    71  // LineStrBuilder is a utility class for building strings line by line
    72  type LineStrBuilder []string
    73  
    74  // AppendLine works like append in that it returns an instance of a LineStrBuilder with the contents updated to contain
    75  // the additional line. lsb = lsb.AppendLine("n: %d, s: %s", n, s)
    76  func (lsb LineStrBuilder) AppendLine(strFmt string, args ...interface{}) LineStrBuilder {
    77  	updated := append(lsb, fmt.Sprintf(strFmt, args...))
    78  	return updated
    79  }
    80  
    81  // String returns the built string with all lines separated by newlines
    82  func (lsb LineStrBuilder) String() string {
    83  	s := strings.Join(lsb, "\n")
    84  	return s
    85  }