match

part of shnell – a source to source compiler enhancement tool

© Jens Gustedt, 2017

Utilities for shell level regexp matching.

Coding and configuration

The following code is needed to enable the sh-module framework.

SRC="$_" . "${0%%/${0##*/}}/import.sh"

Imports

The following sh-modules are imported:

• echo

Details

We provide environment variables for certain tools.

export SED=${SED:=sed}
export SEDU=${SEDU:=-u}
export CAT=${CAT:=cat}
if [ ! "${PAGER}" ] ; then
    PAGER=`whereis -b "less"`
    if [ "${PAGER}" != "less:" ] ; then
        export PAGER="less -R"
    else
        PAGER=`whereis -b "more"`
        if [ "${PAGER}" != "more:" ] ; then
            export PAGER="more"
        else
            export PAGER="${CAT}"
        fi
    fi
fi

The matching we do requires UTF-8 capacities, so we try to set LC_LANG to a UTF-8 locale.

Declared functions

match: Check if string $2 matches regexp $1

This uses shell pattern matching and can be used more simply than the shell’s case construct on which it is built. It can be used as simple prefix conditionals

```cpp match “*[a-z]*” “${id}" || echo "${id} is not an identifier”

or in if-then-else constructs

#if match “*[a-z]*” “${id}" ; then echo "${id} is not an identifier” fi

hasBlank: Test if a list given as an argument has more than one member

replace: In $1, replace the occurences of string $2 by the string $3

The modified string is returned in the variable rplret. ### sed3: A sed that reads the commands from fd 3 As usual this reads the text to be processed from stdin. ### sed2: A sed that reads the commands from $1 and the text from the remaining arguments

realpath: Shortcut “./” and “../” elements in pathnames.