added all shell configuration files

shell/helpers/path_helpers.sh

@@ -0,0 +1,148 @@
+#
+# PATH Helpers
+#
+# A few useful functions to manipulate the PATH environment variable. Use,
+# modify, copy, steal, plunder these functions to your hearts content, at
+# your own risk of course :) --jimeh
+#
+
+
+# Print PATH as a newline separated list.
+#
+# Example:
+#
+#   $ echo $PATH
+#   /usr/bin:/usr/local/bin
+#   $ path_list
+#   /usr/bin
+#   /usr/local/bin
+#
+path_list () {
+    echo -n "$PATH" | tr ":" "\n"
+}
+
+# Append specified path to the end of PATH.
+#
+# Takes one argument:
+#  - $1: path to add
+#
+# If $1 already exists it is first removed, and then added to the end of PATH.
+#
+# Example:
+#
+#   $ echo $PATH
+#   /usr/bin:/usr/local/bin
+#   $ path_append "/usr/sbin"
+#   $ echo $PATH
+#   /usr/bin:/usr/local/bin:/usr/sbin
+#
+path_append () {
+    if [ ! -n "$1" ]; then return 2; fi
+    path_remove "$1";
+    export PATH="$PATH:$1";
+}
+
+# Prepend specified path to the begnning of PATH.
+#
+# Takes one argument:
+#  - $1: path to add
+#
+# If $1 already exists it is first removed, and then added to the beginning of
+# PATH.
+#
+# Example:
+#
+#   $ echo $PATH
+#   /usr/bin:/usr/local/bin
+#   $ path_prepend "/usr/sbin"
+#   $ echo $PATH
+#   /usr/sbin:/usr/bin:/usr/local/bin
+#
+path_prepend () {
+    if [ ! -n "$1" ]; then return 2; fi
+    path_remove "$1";
+    export PATH="$1:$PATH";
+}
+
+# Remove specified path from PATH.
+#
+# Takes one argument:
+#  - $1: path to remove
+#
+# Example:
+#
+#   $ echo $PATH
+#   /usr/bin:/usr/local/bin
+#   $ path_remove "/usr/local/bin"
+#   $ echo $PATH
+#   /usr/bin
+#
+path_remove () {
+    if [ ! -n "$1" ]; then return 2; fi
+    if [[ ":$PATH:" == *":$1:"* ]]; then
+        export PATH=$(__path_clean `echo -n ":$PATH:" | sed "s;:$1;;"`)
+        return 0
+    fi
+    return 1
+}
+
+# Add a path to PATH before another path.
+#
+# Takes two arguments:
+#  - $1: path to add
+#  - $2: target path to add $1 before
+#
+# If $1 already exists in PATH it is first removed, and then added before $2.
+#
+# Example:
+#
+#   $ echo $PATH
+#   /usr/bin:/usr/local/bin
+#   $ path_add_before "/usr/local/sbin" "/usr/local/bin"
+#   $ echo $PATH
+#   /usr/bin:/usr/local/sbin:/usr/local/bin
+#
+path_add_before () {
+    if [ ! -n "$1" ] || [ ! -n "$2" ]; then return 2; fi
+    if [[ ":$PATH:" == *":$2:"* ]]; then
+        path_remove "$1"
+        export PATH=$(__path_clean `echo -n ":$PATH:" | sed "s;:$2;:$1:$2;"`)
+        return 0
+    fi
+    return 1
+}
+
+# Add a path to PATH after another path.
+#
+# Takes two arguments:
+#  - $1: path to add
+#  - $2: target path to add $1 after
+#
+# If $1 already exists in PATH it is first removed, and then added after $2.
+#
+# Example:
+#
+#   $ echo $PATH
+#   /usr/bin:/usr/local/bin
+#   $ path_add_before "/usr/local/sbin" "/usr/local/bin"
+#   $ echo $PATH
+#   /usr/bin:/usr/local/bin:/usr/local/sbin
+#
+path_add_after () {
+    if [ ! -n "$1" ] || [ ! -n "$2" ]; then return 2; fi
+    if [[ ":$PATH:" == *":$2:"* ]]; then
+        path_remove "$1"
+        export PATH=$(__path_clean `echo -n ":$PATH:" | sed "s;:$2;:$2:$1;"`)
+        return 0
+    fi
+    return 1
+}
+
+# Strips first and last character from intput string.
+#
+# Example:
+#   __path_clean ":/bin:/usr/bin:" #=> /bin:/usr/bin
+#
+__path_clean () {
+    echo -n "$1" | sed "s/.\(.*\)./\1/"
+}