few helper functions in bash
#repeatString repeats a string
repeatString string ?depth
#depth >> how many times to repeat the string
repeatString "bash" 5 # bashbashbashbashbash#charAt
get the position of a character in a string
charAt string positionToSearch
charAt "bash" 2 # a#includes
check if a word is in a string
includes string stringToSearch ?depth
#depth where to start search from
includes "bash" sh 2
#returns 1 for false or 0 for true#endsWith check if a word is at the end of a string
endsWith string endToCheck ?depth
# depth >> where to start the search from
endsWith "bash" a 2
#returns 1 for false or 0 for true#isInteger check if a value is an integer
isInteger number
#return 1 for non integers or 0 for integers
#int get all the integers before the decimal point non integers values will throw an error
int number
int 25.8 ; # 25#destructure
set the content of an array into different variables
gotchas
do not quote the array argument ( first agument )
it is important you quote the second argument to this function
associative arrays work in alphabetical order
use "," to separate the variables to assign each array element to
destructure array values
array=( bash ksh zsh )
destructure ${array[@]} "shell1,,shell2"
echo $shell1 # bash
echo $shell2 # zsh
destructure ${array[@]} "shell1,shell2,shell3"
echo $shell1 # bash
echo $shell2 # ksh
echo $shell3 # zsh
#... Spread a bunch of string inside an array
... string
str=bash
array=( $(... $str) )
echo ${str[@]} # b a s h#foreach foreach element of an array execute a function
gotchas:
don't quote the array arugment ( i.e the first argument )
If you pass in a function as a callback using the function command you should wrap it in single quote
s() { echo $(( $1 * $1 )) ;}
array=( 1 2 3 4 5 6 )
foreach ${array[@]} s # 2 4 6 8 10 12
foreach ${array[@]} 'function s() { echo $(( $1 + $1 )) ;}' # always end the function with a ;}
# 2 4 6 8 10 12
#copyWithin copy an array index into another index quote the first argument use ${array[*]} instead of ${array[@]}
copyWithin arrayArgument indexToCopyfrom indexToCopyTo
array=( "bash" "ksh" "zsh" "csh" )
copyWithin "${array[*]}" 1 3 # bash ksh zsh ksh