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--- shell_dump_function [2019/10/24 08:26] – rpjday
+++ shell_dump_function [2019/10/24 23:44] (current) – rpjday
@@ Line 1: / Line 1: @@
-To save piles of typing when debugging scripts:
+To save piles of typing when debugging bash scripts, a dump() function that understands both regular and associative arrays:
 <code>
-dump () {
+is_array() {
-    for v in "$@"; do
+    if [ -n "$BASH" ]; then
-        eval "echo ${v} = \$${v}";
+        declare -p ${1} 2> /dev/null | grep 'declare \-a' >/dev/null && return 0
+    fi
+    return 1
+}
+is_hash() {
+    if [ -n "$BASH" ]; then
+        declare -p ${1} 2> /dev/null | grep 'declare \-A' >/dev/null && return 0
+    fi
+    return 1
+}
+dump() {
+    for var; do
+        if is_array ${var} ; then
+            echo ${var} = $(eval "echo \${${var}[@]}")
+        elif is_hash ${var} ; then
+            dump_hash ${var}
+        else
+            echo ${var} = $(eval "echo \$${var}")
+        fi
+    done
+}
+dump_hash() {
+    h=${1}
+    for k in $(eval "echo \${!${h}[@]}"); do
+        echo "$h[${k}]" = $(eval "echo \${${h}[${k}]}")
     done
 }
 </code>
-Then:
+First, it can dump regular variables:
 <code>
-$ dump PATH HOME
+$ dump HOME HISTFILE HISTSIZE
-PATH = /home/rpjday/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:/usr/local/go/bin:/home/rpjday/bin:/home/rpjday/go1.11.4/go/bin
 HOME = /home/rpjday
+HISTFILE = /home/rpjday/.bash_history
+HISTSIZE = 1000
+$
+</code>
+Next, dumping regular arrays:
+<code>
+$ people=(fred barney wilma betty)
+$ dump people
+people = fred barney wilma betty
+$
+</code>
+Finally, dump a bash associative array:
+<code>
+$ declare -A wife
+$ wife[fred]=wilma
+$ wife[barney]=betty
+$ dump wife
+wife[fred] = wilma
+wife[barney] = betty
+$
 </code>