2. Syntax

IMPR_CONCEPT (
    ◇ FORMAT =/"MED" (by default),
               /"RESULTAT ",
    ◇ UNITE = unit (default: 80),
    # If: equal_to (" FORMAT ", 'MED')
        ◇ VERSION_MED =/"3.3.1" (by default),
                        /"4.0.0",
                        /"4.1.0",
    ◆ CONCEPT = _F (
         ◆/CHAM_MATER = cham_master,
           /CARA_ELEM = cara_elem,
           /CHARGE = char_meca,
         # If: exists (" CARA_ELEM ")
             ◇ REPERE_LOCAL =/"NON" (by default),
                              /"ELEM ",
                              /"ELNO ",
             # If: not equal_to (" REPERE_LOCAL ", 'NON')
                 ◆ MODELE = model,
      ),
    ◇ INFO =/1 (by default),
             /2,
)

◆: mandatory
◇: optional
: present by default
&: together
/: only one among
|: several possible choices