class THaVarList: public TList

 Remove all variables from the list.

 Define a global variable with given type.
 Duplicate names are not allowed; if a name already exists, return NULL

 Define variable via its ROOT RTTI

 Add all variables specified in 'list' to the list. 'list' is a C-style
 structure defined in VarDef.h and must be terminated with a NULL name.

 Allows definition of:
    scalers
    fixed size arrays
    variable size arrays
    fixed size arrays of pointers
    variable size arrays of pointers
 Data can be anywhere in memory, typically in member variables.
 Data type must be specified explicitly. To use the ROOT RTTI features
 to determine data types (and arrays sizes etc.) automatically, or
 to access data in member ROOT objects, use the second form of this
 method.

 The names of all newly created variables will be prefixed with 'prefix',
 if given.  Error messages will include 'caller', if given.
 Output a warning if a name already exists.  Return values >0 indicate the
 number of variables defined, <0 indicate errors (no variables defined).

 Add all variables specified in 'list' to the list. 'list' is a C-style
 structure defined in VarDef.h and must be terminated with a NULL name.

 Allows definition of:
    scalers
    fixed size arrays
    variable size arrays

 Data must be persistent ROOT data members or accessible via
 member functions. They can be member variables, member variables
 of member ROOT objects, or member variables of ROOT objects
 contained in member ROOT containers derived from TSeqCollection.

 The names of all newly created variables will be prefixed with 'prefix',
 if given.  Error messages will include 'caller', if given.
 Output a warning if a name already exists.  Return values >0 indicate the
 number of variables defined, <0 indicate errors (no variables defined).

 Find a variable in the list.  If 'name' has array syntax ("var[3]"),
 the search is performed for the array basename ("var").

 Print variable names, descriptions, and data.
 Identical to Print() except that variable data is also printed.
 Supports selection of subsets of variables via 'option'.
 E.g.: option="var*" prints only variables whose names start with "var".

 Remove a variable from the list
 Since each name is unique, we only have to find it once
 Returns 1 if variable was deleted, 0 is it wasn't in the list

 Remove all variables matching regular expression 'expr'. If 'wildcard'
 is true, the more user-friendly wildcard format is used (see TRegexp).
 Returns number of variables removed, or <0 if error.

 Define() with reference to variable

 Define() with pointer to variable

Avoid ambiguity - cannot specify variable length char array like this
Must use the form with description