Use the readarray Builtin

zpmod provides a readarray builtin (bash-like) to read records into an indexed array.

Basic usage:

print -r -- $'a\nb\nc' | readarray A
print -r -- ${#A[@]}  # => 3

Common options:

Option	Meaning
-d X	Record delimiter (default newline)
-t	Trim trailing delimiter from each record
-n N	Read at most N records
-O I	Start assigning at index I (1-based)
-s N	Skip first N records
-u FD	Read from file descriptor FD
-C cb	Call callback after each quantum batch
-c Q	Batch size for -C (default 5000)

Examples:

# Custom delimiter, keep delimiters
print -nr -- 'x,y,z,' | readarray -d , B
print -r -- ${B[@]}   # 'x,' 'y,' 'z,' ''
 
# Custom delimiter, trim (-t)
print -nr -- 'x,y,z,' | readarray -t -d , B
print -r -- ${B[@]}   # x y z ''
 
# Start at index 5
B=(1 2 3 4)
print -r -- $'a\nb' | readarray -O 5 B
# B -> (1 2 3 4 a b)

See full details in Reference › Builtins.