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Diffstat (limited to 'rt/m4/rt_expand_var.m4')
| -rw-r--r-- | rt/m4/rt_expand_var.m4 | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/rt/m4/rt_expand_var.m4 b/rt/m4/rt_expand_var.m4 new file mode 100644 index 000000000..cec884abc --- /dev/null +++ b/rt/m4/rt_expand_var.m4 @@ -0,0 +1,18 @@ +dnl +dnl @synopsis RT_EXPAND_VAR(baz, $fraz) +dnl +dnl Iteratively expands the second parameter, until successive iterations +dnl yield no change. The result is then assigned to the first parameter. +dnl +dnl This code is heavily borrowed from the Apache 2 codebase. +dnl + +AC_DEFUN([RT_EXPAND_VAR],[ + ap_last='' + ap_cur='$2' + while test "x${ap_cur}" != "x${ap_last}"; do + ap_last="${ap_cur}" + ap_cur=`eval "echo ${ap_cur}"` + done + $1="${ap_cur}" +]) |