[PIG-1244] parameter syntax in scripts, add support for ${VAR} (in addition to current $VAR)

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 0.12.0
• Component/s: impl

Environment

all

• Hadoop Flags: Reviewed
• Assignee: Xuefu Zhang
• Reporter: Alejandro Abdelnur
• Created: 19/Feb/10 00:51
• Updated: 31/Jan/14 18:24
• Resolved: 31/Jan/14 18:23

Description

Currently parameter syntax in pig scripts is $VAR.

This complicates scripts as parameter-literal concatenation is not supported. For example:

An occurrence of '$OUT_tmp' in a script resolves to a parameter 'OUT_tmp', it would be desirable this to resolve to a contactenation of $OUT&_tmp

This can be solved by supporting parameter syntax ${VAR}, so the pig parser can identify the end of the parameter name.

Adding support for ${VAR} syntax in addition of $VAR would maintain backwards compatibility. Changing to syntax ${VAR} syntax will break backwards compatibility.

Issue Links

• depends upon: PIG-1618 Switch to new parser generator technology