Bash array appending element issue

Question

I have an array

declare -a her=("ger" "blr" "tyg" "") for i in "${her[@]}"; do echo $i done 

I get

ger blr tyg 

But when I try and append to an array I get one long string with no spaces

declare -a you #without quotes and with quotes #' " same result for i in {"fgt","fe","ger"}; do you+=${i} done for i in "${you[@]}"; do $i done Fgtfeger 

Any insight on whats happening ? Kinda makes them not as useful

Answer 1

Use Array Compound Assignment Syntax; Otherwise Use Length as Index

You have to append to an array using either the compound assignment syntax (e.g. foo=("elem1" ...) or an array index.

Array Compound Assignment Syntax

The form with parentheses allows you to insert one or more elements at a time, and is (arguably) easier to read. For example:

# start with a clean slate unset you for i in "fgt" "fe" "ger"; do you+=("$i") done printf "%s\n" "${you[@]}" 

This yields the values you'd expect:

fgt fe ger 

Insert at Index Length

You can get similar results by assigning to an index. For example:

unset you for i in "fgt" "fe" "ger"; do you[${#you[@]}]="$i" done printf "%s\n" "${you[@]}" 

This second example works because Bash arrays are zero-indexed, so the length of the array is also the next available index that should be assigned when appending.