guideline

Use action verbs for procedures and entries.

Use predicate clauses for Boolean functions.

Use nouns for non-Boolean functions.

Give packages names that imply a higher level of organization than subprograms. Generally, these are noun phrases that describe the abstraction provided.

Give tasks names that imply an active entity.

Use nouns descriptive of the data being protected for protected units.

Consider naming generic subprograms as if they were nongeneric subprograms.

Consider naming generic packages as if they were nongeneric packages.

Make the generic names more general than the instantiated names.

The following are sample names for elements that compose an Ada program:

Sample procedure names:

procedure Get_Next_Token          -- get is a transitive verb
procedure Create                  -- create is a transitive verb

Sample function names for Boolean-valued functions:

function Is_Last_Item             -- predicate clause
function Is_Empty                 -- predicate clause

Sample function names for non-Boolean-valued functions:

function Successor                -- common noun
function Length                   -- attribute
function Top                      -- component

Sample package names:

package Terminals is               -- common noun
package Text_Routines is           -- common noun

Sample protected objects:

protected Current_Location is      -- data being protected
protected type Guardian is         -- noun implying protection

Sample task names:

task Terminal_Resource_Manager is  -- common noun that shows action

The following sample piece of code shows the clarity that results from using the parts-of-speech naming conventions:

Get_Next_Token(Current_Token);
case Current_Token is
   when Identifier =>         Process_Identifier;
   when Numeric    =>         Process_Numeric;
end case;  -- Current_Token
if Is_Empty(Current_List) then
   Number_Of_Elements := 0;
else
   Number_Of_Elements := Length(Current_List);
end if;

When packages and their subprograms are named together, the resulting code is very descriptive:

if Stack.Is_Empty(Current_List) then
   Current_Token := Stack.Top(Current_List);
end if;

rationale

Using these naming conventions creates understandable code that reads much like natural language. When verbs are used for actions, such as subprograms, and nouns are used for objects, such as the data that the subprogram manipulates, code is easier to read and understand. This models a medium of communication already familiar to a reader. Where the pieces of a program model a real-life situation, using these conventions reduces the number of translation steps involved in reading and understanding the program. In a sense, your choice of names reflects the level of abstraction from computer hardware toward application requirements.