[examples] write expressions intro example

bin/build_examples.sh

@@ -11,6 +11,10 @@ bin/bld_core.sh show_ctx
 
 examps="examples"
 
+bin/bld_core.sh unit expr_intro     $examps/expr/expr_intro.c
+
+exit
+
 bin/bld_core.sh unit hello_world    $examps/intro/hello_world.c
 bin/bld_core.sh unit parse_check    $examps/intro/parse_check.c
 bin/bld_core.sh unit data_desk_like $examps/intro/data_desk_like_template.c

bin/run_examples.sh

@@ -8,6 +8,12 @@ root_path=$PWD
 build_path=$root_path/build
 examps=$root_path/examples
 
+echo ~~~ Running Expression Intro ~~~
+$build_path/expr_intro.exe $examps/expr/expr_intro.mdesk
+echo
+
+exit
+
 echo ~~~ Running Type Metadata Generator Example ~~~
 cd $examps/type_metadata/generated
 $build_path/type_metadata.exe $examps/type_metadata/types.mdesk