></a><code><span><span class="keyword">val</span> subst_param_expr : <span><span><a href="#type-expr">expr</a> <a href="../../../../../Subst/index.html#type-t">Subst.t</a></span> <span class="arrow">&#45;&gt;</span></span> <span><a href="#type-expr">expr</a> <span class="arrow">&#45;&gt;</span></span> <a href="#type-expr">expr</a></span></code></div><div class="spec-doc"><p><code>subst_expr phi e</code> applies substitution <code>phi</code> to expression <code>e</code>, substituting each occurrence of <em>p