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AndrewKushnir
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LGTM 👍 Thanks for the fix Alex!
kara
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LGTM too, though looks like one more compliance test needs to be updated (CI is unhappy)
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Previously, ternary expressions were emitted as: condExpr ? trueCase : falseCase However, this causes problems when ternary operations are nested. In particular, a template expression of the form: a?.b ? c : d would have compiled to: a == null ? null : a.b ? c : d The ternary operator is right-associative, so that expression is interpreted as: a == null ? null : (a.b ? c : d) when in reality left-associativity is desired in this particular instance: (a == null ? null : a.b) ? c : d This commit adds a check in the expression translator to detect such left-associative usages of ternaries and to enforce such associativity with parentheses when necessary. A test is also added for the template type-checking expression translator, to ensure it correctly produces right-associative expressions for ternaries in the user's template. Fixes angular#34087
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) Previously, ternary expressions were emitted as: condExpr ? trueCase : falseCase However, this causes problems when ternary operations are nested. In particular, a template expression of the form: a?.b ? c : d would have compiled to: a == null ? null : a.b ? c : d The ternary operator is right-associative, so that expression is interpreted as: a == null ? null : (a.b ? c : d) when in reality left-associativity is desired in this particular instance: (a == null ? null : a.b) ? c : d This commit adds a check in the expression translator to detect such left-associative usages of ternaries and to enforce such associativity with parentheses when necessary. A test is also added for the template type-checking expression translator, to ensure it correctly produces right-associative expressions for ternaries in the user's template. Fixes #34087 PR Close #34221
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Previously, ternary expressions were emitted as:
condExpr ? trueCase : falseCase
However, this causes problems when ternary operations are nested. In
particular, a template expression of the form:
a?.b ? c : d
would have compiled to:
a == null ? null : a.b ? c : d
The precedence here is incorrect:
a == null ? null : (a.b ? c : d)
when in reality the desired association is:
(a == null ? null : a.b) ? c : d
This commit adds parentheses when emitting ternary operations to preserve
the desired precedence.