What are the attributes passed down from parent nodes to child nodes in a parse tree, allowing for the propagation of information?

What are the attributes passed down from parent nodes to child nodes in a parse tree, allowing for the propagation of information?

• A. Inherited Attributes
• B. Synthesized Attributes
• C. Global Attributes
• D. Local Attributes

Answer: (A)

Inherited attributes are the attributes that flow from a node’s parent to its children in a parse tree, carrying information that must be available to the subtrees as they are analyzed. This downward propagation is what enables context-sensitive information—such as the expected type of an expression, the current scope or symbol-table context, or other environmental data—to be available to each child node when computing its own attributes. For example, when analyzing a function call, the type expectations or available parameter types can be passed down to the argument expressions through inherited attributes. In contrast, synthesized attributes move upward from children to the parent, used to compute a node’s value based on its children. Global or local attributes aren’t standard terms for this downward flow and don’t by themselves describe the direction of information propagation.

Inherited attributes are the attributes that flow from a node’s parent to its children in a parse tree, carrying information that must be available to the subtrees as they are analyzed. This downward propagation is what enables context-sensitive information—such as the expected type of an expression, the current scope or symbol-table context, or other environmental data—to be available to each child node when computing its own attributes. For example, when analyzing a function call, the type expectations or available parameter types can be passed down to the argument expressions through inherited attributes. In contrast, synthesized attributes move upward from children to the parent, used to compute a node’s value based on its children. Global or local attributes aren’t standard terms for this downward flow and don’t by themselves describe the direction of information propagation.