1 Informal Description ¶

It was early recognized that a shorter alternative representation the of-symbol was very much needed, considering the fact the bold version of is at least four characters long. This makes certain phrases long and also slightly laborious to read, like in:

pub op + = (Pos a,b) Pos: (c of a + c of b, r of a + r of b),
       - = (Pos a,b) Pos: (c of a - c of b, r of a - r of b);

In his “ALGOL 68 Hardware Representation Recommendations” [AB42.4.2] Wilfred J. Hansen describes different proposals for shorter alternative representations of the of-symbol which came out during the preparation of the Standard Hardware Representation.

Of these, the preferred one was to use the apostrophe character ', because:

• Apostrophe is a worthy character.
• It is unused out of string and character denotations.
• It is just one character long.

The proposal was not carried on in the Standard Hardware Representation because it is fundamentally not compatible with the QUOTE stropping regime, which was widely used back then. It is unlikely implementations of GNU Algol 68 will support QUOTE stropping however.

Using the brief form of selection, the example above now becomes:

pub op + = (Pos a,b) Pos: (c'a + c'b, r'a + r'b),
       - = (Pos a,b) Pos: (c'a - c'b, r'a - r'b);