2. Syntax

crack_bottom = DEFI_FOND_FISS (
    ◆ MAILLAGE = mesh,
    ◇ INFO =/1 (by default),
             /2,
    ◆ FOND_FISS = _F (
         ◇ TYPE_FOND =/"OUVERT" (by default),
                       /"FERME ",
         ◆/GROUP_NO = grno,
           /GROUP_MA = grma,
         # If: exists (" GROUP_MA ") and not equal_to (" TYPE_FOND ", 'FERME')
             ◇ GROUP_NO_ORIG = big,
             # If: exists (" GROUP_NO_ORIG ")
                 ◇ GROUP_NO_EXTR = big,
         # If: exists (" GROUP_MA ") and equal_to (" TYPE_FOND ", 'FERME')
             ◇ GROUP_NO_ORIG = big,
             # If: exists (" GROUP_NO_ORIG ")
                 ◇ GROUP_MA_ORIG = Grma,
      ),
    ◆ SYME =/"OUI ",
             /"NON ",
    ◆ LEVRE_SUP = _F (
         ◆ GROUP_MA = GRMA,
      ),
    # If: exists (" LEVRE_SUP ") and equal_to (" SYME ", 'NON')
        ◆ LEVRE_INF = _F (
             ◆ GROUP_MA = GRMA,
          ),
    ◇ CONFIG_INIT =/"COLLEE" (by default),
                    /"DECOLLEE ",
    # If: equal_to (" CONFIG_INIT ", 'DECOLLEE')
        ◆ NORMALE = float,
    ◇ PREC_NORM = float (default: 0.1),
)

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