Use the parser for more input parameters (#1481)

* option to smart-query input arguments using the parser

* modify one example to illustrate

* cleaner naming

* cleaner call to the parser, no need to go through a pointer

* better naming and more doc for queryWithParser

* update the documentation

1 files changed, 19 insertions, 1 deletions

diff --git a/Source/Utils/WarpXUtil.cpp b/Source/Utils/WarpXUtil.cpp
index 7a584f6e1..4372c132e 100644
--- a/Source/Utils/WarpXUtil.cpp
+++ b/Source/Utils/WarpXUtil.cpp
@@ -190,7 +190,6 @@ void Store_parserString(amrex::ParmParse& pp, std::string query_string,
     f.clear();
 }
 
-
 WarpXParser makeParser (std::string const& parse_function, std::vector<std::string> const& varnames)
 {
     WarpXParser parser(parse_function);
@@ -213,6 +212,25 @@ WarpXParser makeParser (std::string const& parse_function, std::vector<std::stri
     return parser;
 }
 
+int
+queryWithParser (amrex::ParmParse& a_pp, char const * const str, amrex::Real& val)
+{
+    // call amrex::ParmParse::query, check if the user specified str.
+    std::string tmp_str;
+    int is_specified = a_pp.query(str, tmp_str);
+    if (is_specified)
+    {
+        // If so, create a parser object and apply it to the value provided by the user.
+        std::string str_val;
+        Store_parserString(a_pp, str, str_val);
+
+        auto parser = makeParser(str_val, {});
+        val = parser.eval();
+    }
+    // return the same output as amrex::ParmParse::query
+    return is_specified;
+}
+
 /**
  * \brief Ensures that the blocks are setup correctly for the RZ spectral solver
  * When using the RZ spectral solver, the Hankel transform cannot be