Types

Number Types

\[\begin{split}\begin{array}{llcll@{\qquad\qquad}l} \def\mathdef3786#1{{}}\mathdef3786{number type} & \href{../text/types.html#text-numtype}{\mathtt{numtype}} &::=& \def\mathdef3825#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3825{i32} &\Rightarrow& \href{../syntax/types.html#syntax-valtype}{\mathsf{i32}} \\ &&|& \def\mathdef3826#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3826{i64} &\Rightarrow& \href{../syntax/types.html#syntax-valtype}{\mathsf{i64}} \\ &&|& \def\mathdef3827#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3827{f32} &\Rightarrow& \href{../syntax/types.html#syntax-valtype}{\mathsf{f32}} \\ &&|& \def\mathdef3828#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3828{f64} &\Rightarrow& \href{../syntax/types.html#syntax-valtype}{\mathsf{f64}} \\ \end{array}\end{split}\]

Vector Types

\[\begin{split}\begin{array}{llcll@{\qquad\qquad}l} \def\mathdef3786#1{{}}\mathdef3786{vector type} & \href{../text/types.html#text-vectype}{\mathtt{vectype}} &::=& \def\mathdef3829#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3829{v128} &\Rightarrow& \href{../syntax/types.html#syntax-valtype}{\mathsf{v128}} \\ \end{array}\end{split}\]

Reference Types

\[\begin{split}\begin{array}{llcll@{\qquad\qquad}l} \def\mathdef3786#1{{}}\mathdef3786{reference type} & \href{../text/types.html#text-reftype}{\mathtt{reftype}} &::=& \def\mathdef3830#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3830{funcref} &\Rightarrow& \href{../syntax/types.html#syntax-reftype}{\mathsf{funcref}} \\ &&|& \def\mathdef3831#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3831{externref} &\Rightarrow& \href{../syntax/types.html#syntax-reftype}{\mathsf{externref}} \\ \def\mathdef3786#1{{}}\mathdef3786{heap type} & \href{../text/types.html#text-heaptype}{\mathtt{heaptype}} &::=& \def\mathdef3832#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3832{func} &\Rightarrow& \href{../syntax/types.html#syntax-reftype}{\mathsf{funcref}} \\ &&|& \def\mathdef3833#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3833{extern} &\Rightarrow& \href{../syntax/types.html#syntax-reftype}{\mathsf{externref}} \\ \end{array}\end{split}\]

Value Types

\[\begin{split}\begin{array}{llcll@{\qquad\qquad}l} \def\mathdef3786#1{{}}\mathdef3786{value type} & \href{../text/types.html#text-valtype}{\mathtt{valtype}} &::=& t{:}\href{../text/types.html#text-numtype}{\mathtt{numtype}} &\Rightarrow& t \\ &&|& t{:}\href{../text/types.html#text-vectype}{\mathtt{vectype}} &\Rightarrow& t \\ &&|& t{:}\href{../text/types.html#text-reftype}{\mathtt{reftype}} &\Rightarrow& t \\ \end{array}\end{split}\]

Function Types

\[\begin{split}\begin{array}{llclll@{\qquad\qquad}l} \def\mathdef3786#1{{}}\mathdef3786{function type} & \href{../text/types.html#text-functype}{\mathtt{functype}} &::=& \def\mathdef3834#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3834{(}~\def\mathdef3835#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3835{func}~~t_1^\ast{:\,}\href{../text/conventions.html#text-vec}{\mathtt{vec}}(\href{../text/types.html#text-functype}{\mathtt{param}})~~t_2^\ast{:\,}\href{../text/conventions.html#text-vec}{\mathtt{vec}}(\href{../text/types.html#text-functype}{\mathtt{result}})~\def\mathdef3836#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3836{)} &\Rightarrow& [t_1^\ast] \href{../syntax/types.html#syntax-functype}{\rightarrow} [t_2^\ast] \\ \def\mathdef3786#1{{}}\mathdef3786{parameter} & \href{../text/types.html#text-functype}{\mathtt{param}} &::=& \def\mathdef3837#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3837{(}~\def\mathdef3838#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3838{param}~~\href{../text/values.html#text-id}{\mathtt{id}}^?~~t{:}\href{../text/types.html#text-valtype}{\mathtt{valtype}}~\def\mathdef3839#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3839{)} &\Rightarrow& t \\ \def\mathdef3786#1{{}}\mathdef3786{result} & \href{../text/types.html#text-functype}{\mathtt{result}} &::=& \def\mathdef3840#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3840{(}~\def\mathdef3841#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3841{result}~~t{:}\href{../text/types.html#text-valtype}{\mathtt{valtype}}~\def\mathdef3842#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3842{)} &\Rightarrow& t \\ \end{array}\end{split}\]

Note

The optional identifier names for parameters in a function type only have documentation purpose. They cannot be referenced from anywhere.

Abbreviations

Multiple anonymous parameters or results may be combined into a single declaration:

\[\begin{split}\begin{array}{llclll} \def\mathdef3786#1{{}}\mathdef3786{parameter} & \def\mathdef3843#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3843{(}~~\def\mathdef3844#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3844{param}~~\href{../text/types.html#text-valtype}{\mathtt{valtype}}^\ast~~\def\mathdef3845#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3845{)} &\equiv& (\def\mathdef3846#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3846{(}~~\def\mathdef3847#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3847{param}~~\href{../text/types.html#text-valtype}{\mathtt{valtype}}~~\def\mathdef3848#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3848{)})^\ast \\ \def\mathdef3786#1{{}}\mathdef3786{result} & \def\mathdef3849#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3849{(}~~\def\mathdef3850#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3850{result}~~\href{../text/types.html#text-valtype}{\mathtt{valtype}}^\ast~~\def\mathdef3851#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3851{)} &\equiv& (\def\mathdef3852#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3852{(}~~\def\mathdef3853#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3853{result}~~\href{../text/types.html#text-valtype}{\mathtt{valtype}}~~\def\mathdef3854#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3854{)})^\ast \\ \end{array}\end{split}\]

Limits

\[\begin{split}\begin{array}{llclll} \def\mathdef3786#1{{}}\mathdef3786{limits} & \href{../text/types.html#text-limits}{\mathtt{limits}} &::=& n{:}\href{../text/values.html#text-int}{\def\mathdef3811#1{{\mathtt{u}#1}}\mathdef3811{\mathtt{32}}} &\Rightarrow& \{ \href{../syntax/types.html#syntax-limits}{\mathsf{min}}~n, \href{../syntax/types.html#syntax-limits}{\mathsf{max}}~\epsilon \} \\ &&|& n{:}\href{../text/values.html#text-int}{\def\mathdef3811#1{{\mathtt{u}#1}}\mathdef3811{\mathtt{32}}}~~m{:}\href{../text/values.html#text-int}{\def\mathdef3811#1{{\mathtt{u}#1}}\mathdef3811{\mathtt{32}}} &\Rightarrow& \{ \href{../syntax/types.html#syntax-limits}{\mathsf{min}}~n, \href{../syntax/types.html#syntax-limits}{\mathsf{max}}~m \} \\ \end{array}\end{split}\]

Memory Types

\[\begin{split}\begin{array}{llclll@{\qquad\qquad}l} \def\mathdef3786#1{{}}\mathdef3786{memory type} & \href{../text/types.html#text-memtype}{\mathtt{memtype}} &::=& \mathit{lim}{:}\href{../text/types.html#text-limits}{\mathtt{limits}} &\Rightarrow& \mathit{lim} \\ \end{array}\end{split}\]

Table Types

\[\begin{split}\begin{array}{llclll} \def\mathdef3786#1{{}}\mathdef3786{table type} & \href{../text/types.html#text-tabletype}{\mathtt{tabletype}} &::=& \mathit{lim}{:}\href{../text/types.html#text-limits}{\mathtt{limits}}~~\mathit{et}{:}\href{../text/types.html#text-reftype}{\mathtt{reftype}} &\Rightarrow& \mathit{lim}~\mathit{et} \\ \end{array}\end{split}\]

Global Types

\[\begin{split}\begin{array}{llclll} \def\mathdef3786#1{{}}\mathdef3786{global type} & \href{../text/types.html#text-globaltype}{\mathtt{globaltype}} &::=& t{:}\href{../text/types.html#text-valtype}{\mathtt{valtype}} &\Rightarrow& \href{../syntax/types.html#syntax-mut}{\mathsf{const}}~t \\ &&|& \def\mathdef3855#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3855{(}~\def\mathdef3856#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3856{mut}~~t{:}\href{../text/types.html#text-valtype}{\mathtt{valtype}}~\def\mathdef3857#1{\mbox{‘}\mathtt{#1}\mbox{’}}\mathdef3857{)} &\Rightarrow& \href{../syntax/types.html#syntax-mut}{\mathsf{var}}~t \\ \end{array}\end{split}\]