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Syntax directed translation scheme

• The Syntax directed translation scheme is a context -free grammar.
• The syntax directed translation scheme is used to evaluate the order of semantic rules.
• In translation scheme, the semantic rules are embedded within the right side of the productions.
• The position at which an action is to be executed is shown by enclosed between braces. It is written within the right side of the production.

Example

Production	Semantic Rules
S → E $	{ printE.VAL }
E → E + E	{E.VAL := E.VAL + E.VAL }
E → E * E	{E.VAL := E.VAL * E.VAL }
E → (E)	{E.VAL := E.VAL }
E → I	{E.VAL := I.VAL }
I → I digit	{I.VAL := 10 * I.VAL + LEXVAL }
I → digit	{ I.VAL:= LEXVAL}