Syntax

Declares a map: values stored under text keys. <name>(<key>) reads or writes one entry, <name>() the current one.

NewMap <name>.<type>([<slots>])
NewMap <name>([<slots>])
GLOBAL NewMap <name>.<type>([<slots>])
LOCAL NewMap <name>.<type>([<slots>])
<name>(<key>)
<name>()
<name>(<key>).<field>

Parts

<name>The map's name, with no sigil. It cannot also be the name of a list.
<type>The type of the values, as for NewList: a short suffix, a full type name, or a TYPE name. Without it, the map holds integers.
<slots>Optional size hint kept for PureBasic programs. It must be a positive whole number (0 or less stops the program) and changes nothing else.
<key>The key, as text. A number is turned into text: m(1) and m("1") are the same entry. Keys are case-sensitive.
<field>A field of the entry, for a map of records: bag("sword").qty = 1.

Good to know

  • m("key") = v creates the entry or replaces its value. +=, -=, *= and /= work on an entry.
  • Reading m("key") creates a missing entry with the default value. To test without creating, use FindMapElement().
  • Every access makes that entry the current one. With no current entry, reading m() stops the program: BASIC map has no current element.
  • NewMap m$() is refused at the first use of m(). Write the type after a dot: NewMap m.s().
  • In a program with a DO … LOOP, a FUNCTION does not see a map declared above DO (… is not defined). Declare it with GLOBAL NewMap.

Example

NewMap stock.i()stock("apple") = 3stock("pear") = 5stock("apple") += 2Console(Str(stock("apple")) + " " + Str(MapSize(stock())))   ' 5 2IF FindMapElement(stock(), "plum") = 0 THEN Console("no plum")   ' no plumConsole(Str(stock("plum")) + " " + Str(MapSize(stock())))   ' 0 3
In the manual : Arrays, lists and maps

See also