Implement SPLICE function

[jinlee0]

resolves #1348

[coveralls]

Pull Request Test Coverage Report for Build 5909440080

• 161 of 161 (100.0%) changed or added relevant lines in 6 files are covered.
• 43 unchanged lines in 4 files lost coverage.
• Overall coverage decreased (-0.04%) to 99.154%

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Files with Coverage Reduction	New Missed Lines	%
core/src/ast/mod.rs	1	99.83%
core/src/executor/evaluate/mod.rs	3	99.38%
core/src/executor/execute.rs	9	96.33%
core/src/executor/aggregate/mod.rs	30	84.21%

Totals
Change from base Build 5877755511:	-0.04%
Covered Lines:	49217
Relevant Lines:	49637

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💛 - Coveralls

[jinlee0]

@panarch
I think I'm ready for a review!

[ever0de]

Looks good to me

[ever0de]

Is it correct to create a Quadruple instead of a VariableArgs? @panarch

[panarch]

for now, both can be accepted so this decision which adds Quadruple looks also good.

nit. it would be better to add Quadruple in between Triple and VariableArgs rather than adding it to the last.

[panarch]

Looks all nice! Thanks a lot 👍 👍

[panarch]

for now, both can be accepted so this decision which adds Quadruple looks also good.

nit. it would be better to add Quadruple in between Triple and VariableArgs rather than adding it to the last.