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StringFunctions
  alias · alias_list · head · is_artificial · is_name · is_point_process · left · len · references · right · substr · tail

# StringFunctions (String Manipulation Class)

class `StringFunctions`
  Syntax:
    `obj = new StringFunctions()`
  Description:
    The StringFunctions class contains functions which you can apply to a `strdef`. This class exists purely for the utility of preventing pollution of name space with string operations.

  Example:

  >     objref strobj
  >     strobj = new StringFunctions()

`StringFunctions.``len`()
  Syntax:
    `length = strobj.len(str)`
  Description:
    Return the length of a string.

`StringFunctions.``substr`()
  Syntax:
    `index = strobj.substr(s1, s2)`
  Description:
    Return the index into s1 of the first occurrence of s2. If s2 isn't a substring then the return value is -1.

`StringFunctions.``head`()
  Syntax:
    `strobj.head(str, "regexp", result)`
  Description:
    The result contains the head of the string up to but not including the regexp. returns index of last char.

`StringFunctions.``tail`()
  Syntax:
    `strobj.tail(str, "regexp", result)`
  Description:

    The result contains the tail of the string from the char following regexp to the end of the string. return index of first char.

    Other functions can be added as needed, eg., `index(s1, c1)`, `char(s1, i)`, etc. without polluting the global name space. In recent versions functions can return strings.

`StringFunctions.``right`()
  Syntax:
    `strobj.right(str, n)`
  Description:
    Removes first n characters from str and puts the result in str.

`StringFunctions.``left`()
  Syntax:
    `.left(str, n)`
  Description:
    Removes all but first n characters from str and puts the result in str

`StringFunctions.``is_name`()
  Syntax:
    `.is_name(str)`
  Description:
    Returns 1 if the str is the name of a symbol, 0 otherwise. This is so useful that the same thing is available with the top level `name_declared()` function.

`StringFunctions.``alias`()
  Syntax:

    `.alias(obj, "name", &var2)`

    `.alias(obj, "name", obj2)`

    `.alias(obj, "name")`

    `.alias(obj)`

  Description:
    "name" becomes a public variable for obj and points to the scalar var2 or object obj2. obj.name may be used anywhere the var2 or obj2 may be used. With no third arg, the "name" is removed from the objects alias list. With no second arg, the objects alias list is cleared.

`StringFunctions.``alias_list`()
  Syntax:
    `list = sf.alias_list(obj)`
  Description:
    Return a new List object containing String objects which contain the alias names.

  Warning

  The String class is not a built-in class. It generally gets declared when the nrngui.hoc file is loaded and lives in stdlib.hoc. Note that the String class must exist and its constructor must allow a single strdef argument. Minimally:

      begintemplate String
      public s
      strdef s
      proc init() { s = $s1 }
      endtemplate String

`StringFunctions.``references`()
  Syntax:
    `sf.references(object)`
  Description:
    Prints the number of references to the object and all objref names that reference that object (including references via `HBox`, `VBox`, and `List`). It also prints the number of references found.

`StringFunctions.``is_point_process`()
  Syntax:
    `i = sf.is_point_process(object)`
  Description:
    Returns 0 if the object is not a POINT_PROCESS. Otherwise returns the point type (which is always 1 greater than the index into the `MechanismType(1)` list).

`StringFunctions.``is_artificial`()
  Syntax:
    `i = sf.is_artificial(object)`
  Description:
    Returns 0 if the object is not an ARTIFICIAL_CELL. Otherwise returns the point type (which is always 1 greater than the index into the `MechanismType(1)` list).

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