: Nat → Set can be defined as follows: data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) General form The general form of the definition of a have a datatype Even defined as follows data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) then we can define a function one-not-even : Even 1 → arguments Example 1. You can’t use an irrelevant value in a non-irrelevant context. bad-plus : Nat → .Nat → Nat bad-plus n m = m + n Variable m is declared irrelevant, so it cannot be used here when checking

: Nat → Set can be defined as follows: data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) General form The general form of the definition of a have a datatype Even defined as follows data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) then we can define a function one-not-even : Even 1 → arguments Example 1. You can’t use an irrelevant value in a non-irrelevant context. bad-plus : Nat → .Nat → Nat bad-plus n m = m + n Variable m is declared irrelevant, so it cannot be used here when checking

: Nat → Set can be defined as follows: data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) General form The general form of the definition of a have a datatype Even defined as follows data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) then we can define a function one-not-even : Even 1 → arguments Example 1. You can’t use an irrelevant value in a non-irrelevant context. bad-plus : Nat → .Nat → Nat bad-plus n m = m + n Variable m is declared irrelevant, so it cannot be used here when checking

: Nat → Set can be defined as follows: data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) General form The general form of the definition of a have a datatype Even defined as follows data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) then we can define a function one-not-even : Even 1 → arguments Example 1. You can’t use an irrelevant value in a non-irrelevant context. bad-plus : Nat → .Nat → Nat bad-plus n m = m + n Variable m is declared irrelevant, so it cannot be used here when checking

: Nat → Set can be defined as follows: data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) General form The general form of the definition of a have a datatype Even defined as follows data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) then we can define a function one-not-even : Even 1 → arguments Example 1. You can’t use an irrelevant value in a non-irrelevant context. bad-plus : Nat → .Nat → Nat bad-plus n m = m + n Variable m is declared irrelevant, so it cannot be used here when checking

: Nat → Set can be defined as follows: data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) General form The general form of the definition of a have a datatype Even defined as follows data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) then we can define a function one-not-even : Even 1 → arguments Example 1. You can’t use an irrelevant value in a non-irrelevant context. bad-plus : Nat → .Nat → Nat bad-plus n m = m + n Variable m is declared irrelevant, so it cannot be used here when checking

: Nat → Set can be defined as follows: data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) General form The general form of the definition of a have a datatype Even defined as follows data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) then we can define a function one-not-even : Even 1 → arguments Example 1. You can’t use an irrelevant value in a non-irrelevant context. bad-plus : Nat → .Nat → Nat bad-plus n m = m + n Variable m is declared irrelevant, so it cannot be used here when checking

: Nat → Set can be defined as follows: data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) General form The general form of the definition of a have a datatype Even defined as follows data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) then we can define a function one-not-even : Even 1 → arguments Example 1. You can’t use an irrelevant value in a non-irrelevant context. bad-plus : Nat → .Nat → Nat bad-plus n m = m + n Variable m is declared irrelevant, so it cannot be used here when checking

: Nat → Set can be defined as follows: data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) General form The general form of the definition of a have a datatype Even defined as follows data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) then we can define a function one-not-even : Even 1 → arguments Example 1. You can’t use an irrelevant value in a non-irrelevant context. bad-plus : Nat → .Nat → Nat bad-plus n m = m + n Variable m is declared irrelevant, so it cannot be used here when checking

: Nat → Set can be defined as follows: data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) General form The general form of the definition of a have a datatype Even defined as follows data Even : Nat → Set where even-zero : Even zero even-plus2 : {n : Nat} → Even n → Even (suc (suc n)) then we can define a function one-not-even : Even 1 → arguments Example 1. You can’t use an irrelevant value in a non-irrelevant context. bad-plus : Nat → .Nat → Nat bad-plus n m = m + n Variable m is declared irrelevant, so it cannot be used here when checking